ACTUATOR UNIT

Description

[0001] The invention relates to an actuator unit for generating haptic feedback at a human-machine interface according to the preamble of claim 1. The actuator unit has at least one surface movable in the Z direction and a pressure measuring device for measuring a pressure in the Z direction on this movable surface. Furthermore, a feedback component is provided which is designed to transmit haptic feedback to the movable surface in response to a pressure measured by the pressure measuring device. The actuator unit has contacting means for connecting a control unit which is designed to receive and evaluate pressure measured values ​​from the pressure measuring device and to control the feedback component via the contacting means to generate haptic feedback if a received pressure measured value exceeds a limit value.

[0002] Such an actuator unit can be used in various applications to generate haptic feedback on a surface of a human-machine interface when a certain pressure is applied to the surface. This can be particularly advantageous for creating the perception of a mechanical push button in a user. The haptic feedback can be generated by a feedback component in various ways, for example, using piezoelectric, electromagnetic, and / or electrostatic effects to briefly move a surface from a rest position to a deflected position. Various physical effects can also be used for pressure measurement, for example, capacitive pressure measurement.

[0003] In particular, such haptic feedback is provided in electronic devices on a touchpad or touchscreen. For this purpose, a complex layer structure comprising multiple functional layers is often provided beneath a touch-sensitive surface of an electronic device, as disclosed, for example, in US 2019 / 0391677 A1. However, such a layer structure is firmly integrated into the electronic device and does not represent an independent, separate component that can, for example, be placed at various positions beneath a display. Similar designs are also known from patents FR 3 039 671 A1, US 2018 / 081483 A1, US 2012 / 327025 A1, DE 10 2018 101145 A1, and WO 2019 / 230634 A1.

[0004] The object of the invention is to provide an actuator unit with the most compact possible design for generating haptic feedback on a movable surface, which can be used in particular as an independent component in a human-machine interface.

[0005] According to the invention, this object is achieved by an actuator unit according to independent claim 1. Advantageous further developments of the actuator unit emerge from subclaims 2-14.

[0006] It should be noted that the features listed individually in the claims can be combined with one another in any technically reasonable manner and demonstrate further embodiments of the invention. The description further characterizes and specifies the invention, particularly in conjunction with the figures.

[0007] The actuator unit according to the invention is designed to generate haptic feedback at a human-machine interface. Haptic feedback, in the sense of the present invention, is understood to mean tactile feedback of force to a user who exerts pressure on a surface with their hand, a finger, or a hand-operated aid. A human-machine interface, in the sense of this invention, is understood to mean an interface via which a user can operate and / or control an electronic device. In particular, a pressure- and / or touch-sensitive surface is used, via which a user can operate and / or control an electronic device by contact with the surface. This surface can also be referred to as a contact surface. The surface to be touched is, for example, a touch-sensitive surface of a touchpad or touchscreen.However, the invention can also be used in other types of human-machine interfaces where haptic feedback is advantageous. Tactile feedback is typically provided by a brief deflection of the surface touched by the user, particularly through vibration.

[0008] The actuator unit has at least one surface movable in the Z direction and a pressure measuring device for measuring a pressure in the Z direction on this movable surface. The Z direction runs essentially at an angle of approximately 90° to the movable surface. Furthermore, a feedback component is provided which is designed to transmit haptic feedback to the movable surface in response to a pressure measured by the pressure measuring device, i.e., to cause a brief movement / deflection of the first housing part from a rest position to a deflected position. The feedback component can cause a single or repeated deflection of the movable surface. Suitable damping and return mechanisms bring about a desired oscillation behavior of the movable surface.For this purpose, the actuator unit has contacting means for connecting a control unit which is designed to receive and evaluate pressure measurement values ​​from the pressure measuring device and to control the feedback component to generate haptic feedback if a received pressure measurement value exceeds a limit value.

[0009] The threshold can be a fixed pressure value stored in the control unit. In another embodiment, this threshold is adjustable on the control unit, allowing different thresholds to be set or selected. Furthermore, it is possible to define multiple thresholds and assign different haptic feedback to these thresholds. For example, a user can receive different tactile feedback when applying light pressure to a surface than when applying greater pressure, with one or more intermediate levels also being possible.

[0010] According to the invention, the actuator unit has at least two housing parts, wherein a first housing part forms the movable surface in that the first housing part is arranged to be movable relative to a second housing part at least in the Z direction. The pressure measuring device is then designed to measure a pressure in the Z direction on the movable housing part. The feedback component is arranged between the two housing parts and the pressure measuring device is a capacitive measuring device which is spatially separated from the feedback component and also arranged between the two housing parts in order to effect a capacitive pressure measurement by a movement of the movable first housing part relative to the second housing part in the Z direction. For the movement of the first housing part relative to the second housing part, the feedback component is supported on the second housing part. The deflection of a surface can basically be in the Z direction, i.e.at an angle of 90° to the movable surface, or laterally. In the actuator unit according to the invention, the deflection in the Z direction occurs when the feedback component pushes the first movable housing part away from the second housing part.

[0011] According to the invention, the actuator unit is designed as a stand-alone component that can be installed as a functional component in an electronic device. For example, it can be mounted beneath a surface of a touchpad or touchscreen, with the first movable housing half of the actuator unit being mechanically connected to a touch-sensitive surface. In one embodiment of the invention, multiple actuator units are installed, with four actuator units, for example, being considered, each arranged in a corner of a surface. Other suitable arrangements are, however, also possible. When a user applies pressure to the surface, this pressure is transferred to the first housing part, the movement of which in the direction of the second housing part causes a capacitive pressure measurement by the pressure measuring device.

[0012] The pressure measuring device generates a corresponding pressure measurement value, whereby the pressure measurement value does not necessarily have to be the absolute value of a pressure, but a pressure measurement value can also be given by another parameter which corresponds to the value of a specific pressure or a pressure change. At least this determined pressure measurement value is passed on to the control unit. If the determined pressure measurement value exceeds a certain limit, the control unit assumes that this is not just an unintentional touch by a user, but an intentional actuation pressure. Other parameters can be taken into account in this evaluation by the control unit. The control unit then controls the feedback component via the contact means of the actuator unit, which stimulates the first housing half of the actuator unit to provide haptic feedback through a brief movement or vibration.This excitation is transmitted to the surface of the human-machine interface connected to the first housing half. The position of the surface can be changed translationally, tilted around an axis, and / or locally deformed, for example, by bending. The surface is mounted accordingly, and the actuator unit according to the invention can be used flexibly depending on the installation situation.

[0013] The inventive design of an actuator unit has the advantage that the two housing parts can be used to form a housing for a compact component. The housing parts are preferably made of a non-electrically conductive plastic, and the essential functional components of the actuator unit can be arranged between them. The first movable housing part closes the actuator unit on one side, but also serves to transmit external pressure to the capacitive pressure measuring device and to transmit haptic feedback to a connected surface. The second housing part can be firmly connected to immobile parts of an electronic device during installation.

[0014] The capacitive pressure measuring device is also arranged between the two housing parts, but spatially separated from the feedback component, i.e. they do not overlap, for example. This has the particular advantage that both components can be mounted easily and separately from one another. In one embodiment of the invention, the pressure measuring device and the feedback component lie next to one another as seen in the Z direction. Both components can then, for example, be positioned next to one another on the second housing part before the first housing part is attached to close the actuator unit. Both housing parts are preferably shaped in such a way that an almost closed unit is formed on the outside, which can be easily handled without, for example, individual parts undesirably changing their position.

[0015] Overall, the invention provides an easy-to-assemble, compact actuator unit that can be used in a variety of applications. The actuator unit can be realized in a flat design, for example, with a low height of up to 3 mm, which is advantageous for use in flat display devices. However, larger heights are also possible.

[0016] The feedback component can be configured in various ways based on different physical effects to briefly set the first housing half in motion or even vibrate. For example, the feedback component comprises a piezo structure or voice coil, each of which is designed to cause the first housing part to move in the Z direction. In a piezo structure, the application of a voltage due to the piezo effect causes a mechanical force that is transferred to the first housing part and used to generate a haptic effect. With a voice coil (moving coil), tactile stimuli are transmitted by electromagnetic force.

[0017] In one embodiment of the invention, the actuator unit itself comprises a reset mechanism designed to return the first housing part to its rest position after a deflection from its rest position into a deflected position. The reset mechanism thus counteracts the deflection of the first housing part from the rest position into the deflected position. For this purpose, the reset mechanism comprises, for example, at least one spring element that is clamped under tensile stress between the first housing part and the second housing part. This integration of a reset mechanism into a compact actuator unit has the advantage that the reset is less dependent on the conditions of the installation situation of the actuator unit.In an alternative embodiment, the at least one spring element is not tensioned between the two housing parts of the actuator unit, but rather between the movable first housing part and a part of a human-machine interface into which the actuator unit is installed. In either case, the spring element pulls the first housing part toward the second housing part.

[0018] In a further alternative embodiment, however, the actuator unit is installed in such a way that an external reset mechanism acts on the two housing parts. For example, external spring elements can exert pressure on the first housing part and optionally also on the second housing part in order to reset the first housing part after a deflection by the feedback component toward the second housing part.

[0019] In a preferred embodiment of the invention, at least one damping element is arranged between the feedback component and the second housing part in order to influence and improve the vibration behavior of the system. The damping element is, for example, a rubber component. For example, the damping element is at least partially accommodated in a receptacle within the second housing part. The receptacle is, in particular, a depression in the second housing part that is adapted to the shape and size of the damping element. This contributes to the simple assembly of the actuator unit according to the invention, since the damping element can be inserted into the receptacle before the feedback component is assembled, wherein the damping element is held in position there and, in particular, cannot slip sideways.The damping element extends beyond the edge of the receptacle's opening and contacts the underside of the feedback component in this area. However, the position of the damping element can also be determined in a different way on the second housing part.

[0020] In a preferred embodiment of the invention, the capacitive pressure measuring device comprises at least a first electrode and a second electrode. The first electrode is mechanically connected to the first movable housing part, while the second electrode is mechanically connected to the second housing part. Between the two electrodes there is at least one layer of a dielectric, which dielectric can be formed in various ways. In one embodiment of the invention, the pressure measuring device is designed such that the distance between the two electrodes decreases when pressure is applied to the first housing part, whereby a changing capacitance can be measured in order to determine a pressure measurement value.In alternative embodiments, a design with appropriate force deflections is selected to increase the distance between the two electrodes when pressure is applied to the first housing part and to determine a pressure measurement value from a changing capacitance. The deformation of an electrode and / or a parallel displacement of the two electrodes relative to each other can also be used to determine pressure. However, two parallel electrodes, which are moved toward each other when a force is applied to the electrode on the movable housing part, have the advantage that they can be easily attached to the inside of the two housing parts.

[0021] In one embodiment of the invention, in addition to generating haptic feedback, the feedback component is also designed to measure pressure on the first housing part in the Z direction. When pressure is applied to the first movable housing part, it presses on the feedback component, which can measure this pressure. When using a piezo structure, for example, the piezo structure is mechanically compressed, which can be detected as a voltage change and converted into a pressure measurement. The feedback component then serves not only to generate haptic feedback, but can optionally also be used to measure pressure. With a piezo structure, both the direct piezoelectric effect and the inverse piezoelectric effect are utilized.When pressure is applied to the first movable housing part, the first housing part presses on the feedback component and simultaneously moves the first electrode towards the second electrode of the capacitive pressure measuring device in order to reduce the distance between the electrodes (or increase the distance, deform an electrode, or move electrodes against each other) for a capacitive pressure measurement.

[0022] The pressure measurement of a feedback component such as a piezo structure is dynamic, whereas the pressure measurement of the capacitive pressure measuring device is quasi-static. With capacitive pressure measurement, a specific pressure measurement value results from a position of the electrodes relative to one another, which does not change as long as the position of the housing parts / electrodes relative to one another does not change. This is referred to as static. The pressure measurements determined by both components are suitably processed by the control unit in order to increase the accuracy of the pressure measurement. In one embodiment of the invention, the control unit is therefore designed to determine a reference pressure value for comparison with the limit value from pressure measurements of the capacitive pressure measuring device and pressure measurements of the feedback component.

[0023] Preferably, the functionality of the actuator unit can be configured via the control unit, whereby it can be configured whether the feedback component is used in addition to pressure detection or not. Pressure measurement by the feedback component is therefore considered merely optional, but the actuator unit is designed for this option.

[0024] In order to provide an actuator unit with the simplest possible design that is also easy to install, the feedback component and the pressure measuring device are preferably electrically contacted to the control unit via a common contacting element. This contacting element serves at least to control the feedback component via the control unit and to connect the capacitive pressure measuring device to the control unit. Additionally, it can also be used to connect the feedback component in order to transmit pressure measurements from the feedback component to the control unit. In an advantageous embodiment of the invention, the contacting element used comprises a flat strip made of an electrically insulating material, onto which several contact lines are applied for electrically contacting the feedback component and the pressure measuring device.The band-shaped contacting element can then be electrically connected to the feedback component and the pressure measuring device via connection points.

[0025] In one embodiment of the invention, the contacting element also forms the at least two electrodes of the capacitive pressure measuring device. The electrodes are thus formed on the contacting element and are positioned correctly during assembly of the contacting element. Preferably, the at least one layer of a dielectric between the two electrodes is then formed by the flat strip of the contacting element. The strip-shaped contacting element thus not only provides the electrical contact for the actuator unit but also simultaneously forms the essential components of the capacitive pressure measuring device. This again facilitates the assembly of the actuator unit and contributes to its compactness.

[0026] The two electrodes can be formed and positioned on the contacting element in different ways. For example, the flat strip of the contacting element forms two pressure sections, each with an electrode. One electrode is formed, for example, by a copper layer applied to the flat strip. By deforming the flat strip, it is then possible to position the two pressure sections with the electrodes relative to one another such that they lie parallel to one another in two planes, with at least one layer of the flat strip lying between the two electrodes. Preferably, at least two layers of flat strip lie between the two electrodes and form a dielectric.

[0027] In one embodiment of the invention, the flat strip of the contacting element is shaped, for example by means of openings and / or incisions, such that it has at least one tab strip which is folded over one another at a bending point, wherein a pressure section is formed at each end of the at least one tab strip, on which pressure section a flat electrode is attached such that the two pressure sections made of flat strip lie between the two electrodes. In particular, two such tab strips can be provided, which are folded over one another at a bending point. During manufacture of the contacting element, two pressure sections are thus formed, on which electrodes are formed. The electrodes are initially located on the same side of the flat strip. The two pressure sections are connected to one another via at least one tab strip.If at least one tab strip is folded over at a bending point, the two pressure sections lie parallel to each other, with one of the two electrodes now on the opposite side of the contacting element. The two pressure sections now lie between the two electrodes.

[0028] In this way, the contacting element can be easily manufactured by applying contact lines and electrodes to only one side of a flat strip. By folding over at least one tab strip, the two electrodes are brought into the correct position relative to one another and the contacting element can be mounted. For this purpose, for example, a pressure section with one electrode is first connected to a housing part and during assembly of the other housing part, this is connected to the other pressure section and thus to the other electrode. This can be done, for example, by an adhesive connection. The use of such a contacting element also has the advantage that the capacitive pressure measuring device and the contact of the feedback component can be easily arranged approximately in one plane, which contributes to the low overall height of the actuator unit according to the invention.

[0029] In one embodiment of the invention, the two housing parts are designed in a stepped manner in the area of ​​the electrodes, i.e., the capacitive pressure measuring device. This allows the electrodes to be positioned in a different plane than the feedback component, viewed in the Z direction. The bending point of the at least one tab strip of a contacting element is flexible and yielding, allowing the first electrode to move relative to the second electrode without the bending point breaking under continuous load.

[0030] To simplify the manufacture of the contacting element and the formation of the pressure sections with the electrodes, it is further provided, for example, that the flat strip has a recess within which the at least one folded tab strip is arranged. Contact lines of the contacting element run around the recess to the feedback component and the electrodes of the pressure measuring device. The flat strip of the contacting element then optionally widens in the area of ​​this recess.

[0031] The invention also encompasses a human-machine interface with a surface to which at least one actuator unit according to the invention is connected, in order to generate haptic feedback upon pressure being applied to the surface and transmit it to the surface. The human-machine interface has the control unit, which is connected to one or more actuator units via the respective contacting means. The control unit is configurable for the respective application. For example, one or more pressure limit values ​​can be set in the control unit.

[0032] Further advantages, special features and expedient developments of the invention emerge from the subclaims and the following representation of preferred embodiments with reference to the figures.

[0033] From the illustrations shows: Fig. 1 shows a schematic sectional view of a first embodiment of an actuator unit according to the invention; Fig. 2 shows a schematic sectional view of a second embodiment of an actuator unit according to the invention; Fig. 3 shows a three-dimensional view of an embodiment of a contact of an actuator unit with a band-shaped contacting element; Fig. 4 shows a schematic longitudinal section through a contact according to Fig. 3 ; Fig. 5A a three-dimensional plan view of a contacting element according to Fig. 3 in the unfolded state; Fig. 5B a rear view of the contacting element according to Fig. 5A ; Fig. 6A a three-dimensional plan view of a contacting element according to Fig. 5A in the folded state; Fig. 6B Rear view of the contacting element according to Fig. 6A .

[0034] Fig. 1 shows a schematic sectional view of a first embodiment of an actuator unit 10 according to the invention for generating haptic feedback at a human-machine interface. The essential components and their functions will be explained using this schematic diagram. The interface is not shown in full in the figures, but only the actuator unit 10 and a surface 80 of the human-machine interface. The surface 80 is a pressure- and / or touch-sensitive surface. Furthermore, the upper side of the surface 80 is flat, as in the embodiments of the figures. However, it can also have other shapes and, for example, be curved. The interface is formed, for example, by a touchpad or a touchscreen.The actuator unit 10 is controlled via a control unit 11 of the human-machine interface, whose connection is schematically shown in the figures with a dashed line. Furthermore, the human-machine interface can have one or more actuator units.

[0035] The design of the Fig. 1 provides two housing parts 20 and 21, which together form a housing of the actuator unit 10, in which the essential components of the actuator unit 10 are accommodated. This includes a feedback component 30, which in this embodiment is a piezo structure. Alternatively, a voice coil could also be selected, for example. The first housing part 20 is also referred to as the upper housing part and is movable in the Z direction relative to a second housing part 21, which consequently forms a lower housing part. In the installed situation, the lower housing part 21 is then stationary, while the upper housing part 21 represents the movable side. The possible movement of the upper housing part 20 is in Fig. 1 represented by a double arrow. The upper housing part 20 can be guided relative to the lower housing part 21. For the purpose of explanation, the surface 80 in this embodiment is directly connected to the upper housing part 20, but the mechanical connection can also be designed differently and, for example, include further intermediate elements, supports, suspensions, etc. This is the case with the embodiment of the Fig. 2 and the intermediate element 81, although this is again merely a schematic diagram. The intermediate element can also be implemented in other ways.

[0036] The feedback component 30 is housed between the two housing parts 20, 21, with a damping element 40 located between the feedback component 30 and the lower housing part 21. This damping element 40 is housed in a recess 22 in the lower housing part 21 and protrudes beyond the opening edge of the recess to make contact with the underside of the feedback component 30. On the upper side of the feedback component 30, it rests against an inner surface of the upper housing part 20.

[0037] Furthermore, a capacitive pressure measuring device 60 is formed between the two housing parts 20, 21. Viewed in the Z direction, this pressure measuring device 60 is located next to the feedback component 30, i.e., it is spatially separated from it. The pressure measuring device 60 comprises two flat electrodes 61, 62 and a dielectric 63 located therebetween. A first electrode 61 is connected to the first housing part 20, while a second electrode 62 is connected to the lower housing part 21.

[0038] If pressure is applied to surface 80 in the Z direction (not shown to scale by a hand), this pressure is transferred to the upper housing part 20, causing this housing part 20 to move towards the lower housing part 21. This movement is optionally limited by a stop 25, 26. The distance between the two electrodes 61, 62 of the capacitive pressure measuring device 60 decreases, and the connected control unit 11 can determine a pressure measurement value from the measured capacitance or its change. If this pressure measurement value is greater than a certain limit value, the pressure on surface 80 is interpreted as the user's intended operating pressure. The control unit 11 then controls the feedback component 30 to generate haptic feedback on the upper housing part 20. This haptic feedback is transferred from the upper housing half 20 to surface 80.

[0039] To generate the haptic feedback, for example, a voltage is applied to the piezo structure 30, which is converted into a mechanical force by the inverse piezoelectric effect, which expands the piezo structure 30 and pushes the upper housing part 20 away from the lower housing part 21. The upper housing part 20 thus moves from a rest position to a deflected position. This occurs against the force of one or more clamping components 23, 24. These are designed, for example, as spring elements that are clamped under tensile stress between the two housing parts 20 and 21. The clamping components act as a return mechanism, which returns the upper housing part 20 to its rest position after it has been deflected. Together with the damping element 40, this results in an oscillation system that is suitably selected to produce the desired perception for the user with appropriate excitation by the feedback component on the surface 80.

[0040] Fig. 2 shows a schematic sectional view of a second embodiment of an actuator unit 10', which in essential features corresponds to the embodiment of the Fig. 1 However, two pressure measuring devices 60 and 60' are provided, which are arranged on opposite sides of the feedback component 30. Both pressure measuring devices 60 and 60' each have two electrodes 61, 62 and 61', 62', between which a dielectric 63, 63' is located. In a further alternative embodiment, these are ring-shaped electrodes which surround the feedback component 30. Even in such an embodiment, the pressure measuring device is to be regarded as spatially separated from the feedback component 30, since the ring-shaped electrodes do not overlap with the feedback component 30 in the Z direction.

[0041] Furthermore, no spring elements are provided as clamping components 23, 24, which are clamped between the two housing parts 20, 21. Rather, by installing the actuator unit 10' in an electronic device, the clamping elements 23, 24 act from the outside on the two housing parts 20, 21, thus causing the upper housing part 20 to return to its rest position.

[0042] In the embodiments of the Figuren 1 and 2It can further be provided that the respective feedback component 30 is also used for pressure measurement in addition to the at least one capacitive pressure measuring device 60, 60'. If pressure is applied to the surface 80 and thus to the upper housing part 20, the feedback component 30 also experiences a mechanical force in the Z direction, which compresses the feedback component 30. This is converted into a voltage by the direct piezoelectric effect, from which a pressure measurement value can be determined. The control unit 11 is then designed to evaluate the pressure measurements from the feedback component 30 and the at least one capacitive pressure measuring device 60, 60' in order to improve the overall pressure determination.

[0043] The embodiments of the Figuren 1 and 2illustrate that the actuator unit according to the invention can be designed as a compact component in which a feedback component and also at least one capacitive pressure measuring device can be easily accommodated in a housing consisting of two housing parts. The individual functional components can be aligned on the lower housing part 21 before the upper housing part 20 is mounted. Suitable contacting of the feedback component and the pressure measuring device with the control unit 11 can also contribute to compactness and simple assembly. An advantageous contacting is shown in the Figuren 3 und 4 explained.

[0044] Fig. 3 shows the contacting of a feedback component 30 in the form of a piezo structure. Fig. 4 shows a schematic longitudinal section through this contact. The piezo structure 30 is electrically connected to the control unit 11 in order to control it and optionally also receive pressure signals from it. This contact is made via a special contact element 50, which simultaneously forms the electrodes of at least one capacitive pressure measuring device. The assembly of the Fig. 1 can be done before or after the feedback component 30 is attached to a lower housing part 21.

[0045] The contacting element 50 is formed by a flat strip made of an electrically non-conductive material, on which contact lines are applied for contacting the feedback component and the capacitive pressure measuring device.

[0046] Copper, for example, is chosen for these contact lines. At the same time, the flat strip forms at least two pressure sections, each of which has a flat electrode applied to it. These electrodes can also be made of copper. The flat strip is deformed so that the two flat electrodes lie parallel to each other in two planes, with the pressure sections made of the material of the flat strip located between the two electrodes, thus forming a dielectric.

[0047] In the presentation of the Fig. 3 The contact lines are not visible on the underside of the contacting element 50, which is connected to the control unit 11 by these contact lines. Contact lines lead to two end contact tabs 57 and 58 on the flat strip, which are connected to the piezo structure 30. Further contact lines lead to the two electrodes, of which in the view of the Fig. 3 The upper electrode 61 is visible. This electrode 61 is located at the end of two tab strips 53, 54, which are folded over in the middle. On one tab strip 53, a conductor 74 is routed from the underside of the flat band around the bending point of the tab strip 53 to the electrode 61. Fig. 4 shows the other electrode 62 on the underside of the contacting element 50, which is also contacted via a conductor.

[0048] The two electrodes 61, 62 are arranged so that they are located between the two housing parts during assembly of an actuator unit. The connection to the housing parts can be made, for example, by adhesive bonding. The two housing halves 20, 21 are Fig. 4 shown schematically in dashed lines.

[0049] The contacting element 50 is manufactured in two steps. First, contact lines and electrodes are formed on one side of the flat strip. Subsequently, at least one tab strip is folded over at a bending point to bring the two electrodes into a position parallel to each other. This manufacturing process is described in detail in the Figuren 5A, 5B and 6A, 6B explained in more detail. The Figuren 5A und 5B show the contacting element 50 in the first manufacturing stage, where Fig. 5A the top and Fig. 5B the underside. The flat strip of the contacting element 50 forms a feed section 52, along which all contact lines 70 run. It further forms a recess 51, around which these contact lines 70 run at least partially. At least two conductors 71 and 72 run around the recess 51 up to two contact tabs 57, 58 in the strip, with which the feedback component is contacted.

[0050] In addition, the band forms a first pressure section 56 between the two contact tabs 57, 58, from which two tab strips 53, 54 protrude into the recess 51. At the other end of these tab strips 53, 54, a further pressure section 55 is formed, which connects the two tab strips 53, 54 to one another. A first electrode 62 is formed on the first pressure section 56 and is contacted via a conductor 73 that also runs around the recess 51. A second electrode 61 is formed on the second pressure section 55 and is contacted via a conductor 74 that runs via the tab strip 53 to the electrode 61.

[0051] To form the final contact element, the tab strips 53, 54 are folded approximately 180° at a bending point. This is done so that the two electrodes 61, 62 are then positioned essentially parallel to one another. Fig. 6A shows the result of this second production stage from the top, while Fig. 6B The resulting contact element is shown again from the back. Electrode 61 is now on top and is contacted by conductor 74 around the bend of tab strip 53, while the other electrode 62 and the remaining contact lines 70 are on the opposite side of the flat strip. The two pressure sections 55 and 56 lie between the two electrodes 61, 62 and form a dielectric. List of reference symbols:

[0052] 10, 10'Actuator unit 11Control unit 20,21Housing part 22Receptacle 23,24Clamping component 25,26Stop 30Feedback component, piezo structure 40Damping element 50Contacting element 51Recess 52Feed section 53,54Tab strip 55,56Pressure section 57,58Contact tab 60,60'Pressure measuring device 61,61'Electrode 62,62'Electrode 63,63'Dielectric 70Contact lines 71,72Conductor for feedback component 73,74Conductor for electrode 80Surface 81Intermediate element

Claims

1. Actuator unit (10; 10') for generating haptic feedback at a human-machine interface, having at least: - a surface that is movable in the Z direction; - a pressure-measuring device (60) for measuring a pressure in the Z direction on this movable surface; - a feedback component (30), which is designed to transmit haptic feedback to the movable surface in response to a pressure measured by the pressure-measuring device (60); - contacting means for connecting the actuator unit (10; 10') to a control unit (11), which is designed to receive and to evaluate pressure measurement values of the pressure-measuring device (60) and to actuate the feedback component (30) to generate haptic feedback if a determined pressure measurement value exceeds a limit value; characterized in that - the actuator unit (10; 10') has at least two housing parts (20; 21), as a result of which the actuator unit (10; 10') forms a stand-alone component, which can be installed into an electronic device as a functional component, and the two housing parts (20; 21) form a housing for the component; - a first housing part (20) forms the movable surface by way of the first housing part (20) being arranged movably in relation to a second housing part (21) at least in the Z direction; - the pressure-measuring device (60) is designed to measure a pressure in the Z direction on the movable housing part (20), wherein the pressure-measuring device (60) is a capacitive measuring device which is arranged between the two housing parts (20; 21) in a manner spatially separated from the feedback component (30) in order to cause a capacitive pressure measurement owing to the movable first housing part (20) moving in relation to the second housing part (21) in the Z direction.

2. Actuator unit according to Claim 1, characterized in that the feedback component (30) comprises a piezo structure or oscillator coil, which is designed to cause the first housing part (20) to move in the Z direction.

3. Actuator unit according to one or both of Claims 1 and 2, characterized in that it comprises a return mechanism, which is designed to return the first housing part (20) to its neutral position following a deflection from its neutral position to a deflected position.

4. Actuator unit according to Claim 3, characterized in that the return mechanism comprises at least one spring element, which is clamped under tension between the first housing part (20) and the second housing part (21).

5. Actuator unit according to one or more of Claims 1 to 4, characterized in that at least one damping element (40) is arranged between the feedback component (30) and the second housing part (21).

6. Actuator unit according to Claim 5, characterized in that the damping element (40) is at least partially received in a receptacle (22) within the second housing part (21).

7. Actuator unit according to one or more of Claims 1 to 6, characterized in that the pressure-measuring device (60) has at least one first electrode (61), which is connected to the first movable housing part (20), and at least one second electrode (62), which is connected to the second housing part (21), wherein there is at least one layer of a dielectric between the two electrodes (61; 62).

8. Actuator unit according to one or more of Claims 1 to 7, characterized in that the feedback component (30), in addition to generating haptic feedback, is also designed to measure a pressure on the first housing part (20) in the Z direction.

9. Actuator unit according to Claim 8, characterized in that the control unit (11) is designed to determine a reference pressure value for comparison with the limit value from pressure measurement values of the capacitive pressure-measuring device (60) and pressure measurement values of the feedback component (30).

10. Actuator unit according to one or more of Claims 1 to 9, characterized in that the feedback component (30) and the pressure-measuring device (60) can be electrically contact-connected to the control unit (11) via a common contacting element (50), wherein the contacting element (50) comprises a flat strip composed of an electrically insulating material, on which a plurality of contact lines (70) for electrically contacting the feedback component (30) and the pressure-measuring device (60) are applied.

11. Actuator unit according to any of Claims 7 to 10, characterized in that the contacting element (50) forms the at least two electrodes (61; 62) of the pressure-measuring device (60), wherein at least one layer of a dielectric between the two electrodes (61; 62) is formed by the flat strip of the contacting element (50).

12. Actuator unit according to Claim 11, characterized in that the flat strip of the contacting element (50) is formed, by apertures and / or incisions, such that it has at least one tab strip (53; 54), which is folded up at a bending point, wherein a pressure portion (55; 56) is formed at each of the ends of the at least one tab strip (53; 54), a flat electrode (61; 62) being attached to the pressure portion such that the two pressure portions (55; 56) are situated between the two electrodes (61; 62).

13. Actuator unit according to Claim 12, characterized in that the flat strip has a recess (51) within which the at least one tab strip (53; 54) is arranged, wherein contact lines (70) of the contacting element (50) are routed around the recess (51) to the feedback component (30) and the electrodes (61; 62) of the pressure-measuring device (60).

14. Actuator unit according to one or more of Claims 1 to 13, characterized in that the pressure-measuring device (60) and the feedback component (30) are arranged next to each other as viewed in the Z direction.