Micro-electromechanical coupling devices

Abstract

To identify a micro-mechanical coupling device or ring gyroscope that suppresses translational mode excitation while simultaneously saving installation space compared to known solutions. [Solution] A micro-electromechanical coupling device (100) for coupling micro-electromechanical components, comprising: a flexible ring structure (110) that forms a circle when stationary and is deformable substantially parallel to the plane of the circle and is suitable for coupling the micro-electromechanical components; and a plurality of spring elements (120) suitable for connecting the ring structure (110) to a substrate (200), each spring element (120) comprising: at least one tangential spring (122) that is displaceable substantially tangentially with respect to the ring structure (110); and at least one radial spring (124) that is displaceable substantially radially with respect to the ring structure (110); The spring element (120) has independent components for the tangential spring (122) and the radial spring (124), and the ratio of the spring stiffness of the tangential spring (122) and the radial spring (124) of each spring element (120) is configured such that the vibration that deforms the ring structure (110) is more energetically advantageous than the vibration that displaces the ring structure (110) with respect to the substrate (200) in translation and / or rotation, and / or the natural frequency of the translation and / or rotational vibration and the nearest natural frequency of the deformation vibration are separated by more than 5% of the natural frequency of the deformation vibration.

Description

Technical Field

[0001] [[ID=)4]] The present invention relates to a microelectromechanical coupling device for coupling microelectromechanical components, and a ring gyroscope comprising such a coupling device.

Background Art

[0002] In micro-mechanical measurement devices such as angular velocity sensors and acceleration sensors, in many cases, it is necessary to connect different micro-mechanical components such as vibration systems and masses to each other and couple their respective movements.

[0003] In this case, coupling by a freely floating and unattached ring is often desirable. This is because such a ring responds to the influence of a radial force with a displacement having the same amplitude regardless of which point in the circumferential direction the radial force affects. Similarly, it is also advantageous to use a freely floating ring as an angular velocity sensor. In this case, during rotation, a detected vibration is superimposed on the excitation vibration by the Coriolis force.

[0004] However, the problem here is that without a connection to the substrate of the measurement device, a translational mode, a rotational mode in which the entire ring rotates, or other parasitic modes form the first eigenmode. However, these are not desirable. Furthermore, the manufacture of non-mounted rings for coupling microelectromechanical components involves a great deal of labor from the perspective of manufacturing technology.

[0005] In this case, for example, the use of a system having a plurality of rings connected to each other by highly rigid and short connecting parts (so-called spokes) is known. The spokes themselves are very space-saving. However, in order to be properly attached, a plurality of rings need to be provided, so this space-saving property is partially offset. Furthermore, due to its rigidity, the spokes do not resonate within the range of several kHz. Also, in this design, it is difficult to achieve homogeneous behavior in the circumferential direction.

[0006] As an alternative, very long and therefore space-consuming, but very soft springs are sometimes used. With these, low resonant frequencies can be achieved, but the deviation from the ideal ring is very large and homogeneous behavior in the circumferential direction cannot be achieved. [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] Therefore, an object of the present invention is to identify a micro-mechanical coupling device or ring gyroscope that can suppress translational mode excitation while simultaneously saving installation space compared to known solutions. [Means for solving the problem]

[0008] This objective is achieved by the subject matter of claim 1. A micro-electromechanical coupling device for connecting micro-electromechanical components, comprising: a flexible ring structure suitable for coupling the micro-electromechanical components, which forms a circle when stationary and is deformable substantially parallel to the plane of the circle; and a plurality of spring elements suitable for connecting the ring structure to a substrate, each spring element comprising at least one tangential spring displaceable substantially tangentially with respect to the ring structure and at least one radial spring displaceable substantially radially with respect to the ring structure, wherein the tangential spring and the radial spring of each spring element are independent components, and the ratio of the spring stiffness of the tangential spring to the radial spring of each spring element is such that vibrations that deform the ring structure are more energetically favorable than vibrations that displace the ring structure translationally and / or rotationally with respect to the substrate, and / or the natural frequency of the translational and / or rotational vibration and the closest natural frequency of the deformation vibration are separated by more than 5% from the natural frequency of the deformation vibration. This interval is configured to be within a range of 5% to 200% of the natural frequency of the deformation vibration, more preferably 5% to 100%, and even more preferably 5% to 50%.

[0009] Therefore, the coupling device has a ring as its basic structure, which is mounted above the substrate and has, for example, the shape of a self-contained bar, with its height perpendicular to the substrate being many times its width parallel to the substrate. In its stationary position, this ring forms a circle in the broadest sense, i.e., a closed curve parallel to the substrate. In this case, deformation of the ring is only possible substantially parallel to the substrate, i.e., displacement (deflection) perpendicular to the substrate is negligible to the operation.

[0010] To suppress translational and / or rotational modes or vibrations, the ring structure is connected to the substrate via spring elements consisting of tangential and radial springs, i.e., springs that are displaceable substantially tangentially to the ring structure or perpendicularly to the ring structure (radially). The spring stiffnesses of the tangential and radial springs can be set independently of each other by appropriately sizing the springs during the conceptual design and manufacturing of the coupling device. In this way, the ratio of the spring stiffness of the tangential to the radial spring of each spring element can be set so that other interfering modes, such as translational or rotational modes, are energetically unfavorable compared to at least one "actual" vibration mode, i.e., a vibration mode that deforms the ring structure (hereinafter also referred to as the bending mode). This ensures that the ring structure deforms as desired during excitation and does not merely move laterally.

[0011] Furthermore, or alternatively, by setting the ratio of spring stiffness between tangential and radial springs, it is possible to ensure that the natural frequencies of the translational and / or rotational modes are sufficiently different from the nearest natural frequency of the bending mode. This ensures that, for example, the influence of a force exciting the translational mode does not couple to and interfere with the desired vibration mode. In this way, interference of motion vibrations from the ring structure can be prevented.

[0012] The possibility of achieving the above-mentioned effects by providing tangential and radial springs that act independently of each other can be understood as follows:

[0013] In the first non-translational vibration mode, the ring vibrates in an elliptical shape. At any given moment, this process forms two antinodes, i.e., the positions with the maximum amplitude. Therefore, this mode is also called the n=2 eigenmode. Further bending eigenmodes with multiple antinodes are called n=3, 4, 5... eigenmodes accordingly.

[0014] JPEG2026521833000002.jpg26169

[0015] Therefore, points on the ring experience tangential displacement in addition to radial displacement. In this case, the tangential displacement is at most half the magnitude of the radial displacement. Furthermore, the sum of the radial displacements of each point is greater than the sum of the tangential displacements. This means that the radial displacement is greater than the tangential displacement.

[0016] Some points experience only radial or tangential displacement, while others experience superimposed radial and tangential displacement.

[0017] When spring elements having independently displaceable radial and tangential springs are used to suspend a ring structure, radial and tangential displacements can be controlled via the ratio of the tangential to radial spring stiffnesses of each spring element. The greater the tangential spring stiffness compared to the radial spring stiffness, the less the tangential spring will displace for the same magnitude of force compared to the radial spring. Therefore, if the tangential spring stiffness is higher than that of the radial spring, the ring structure will also be less deformable in the tangential direction than in the radial direction.

[0018] In contrast to the n=2 eigenmodes, during translational motion, the ring does not deform and behaves almost like a rigid body with mass. When a ring structure connected to a substrate by spring elements moves purely translationally on the substrate, only the spring elements deform, and the ring structure does not. The displacement / deformation of these spring elements is different from the displacement of the spring elements in the n=2 eigenmodes. Here, the notion that the tangential displacement is at most half the radial displacement no longer holds true. Furthermore, the sum of the tangential displacements at each point is greater than in the n=2 eigenmode case. In this process, the sum of the radial displacements remains almost unchanged.

[0019] The ring behaves similarly in rotational mode. Here, the ring rotates as a rigid body around its central axis, and only the spring is displaced. In this case, the spring is displaced almost exclusively in the tangential direction.

[0020] Therefore, the translational and rotational modes of the ring structure can be suppressed or shifted to higher frequencies by using independent radial and tangential springs in each spring element, because their separately configurable spring stiffnesses can suppress the tangential displacement of the ring structure by more than half the amount of the radial displacement. Thus, the n=2 eigenmodes can be energetically more favorable than the translational and / or rotational modes.

[0021] The same applies to higher-order bending eigenmodes (n=3,4,5...). These modes, too, can be energetically more favorable than the translational / rotational modes through proper design of the radial and tangential springs of the spring element. Thus, the natural frequencies of the vibrational / bending eigenmodes can also be separated from the natural frequencies of the translational and / or rotational modes by adjusting the spring stiffness.

[0022] The spring element can be designed such that the ratio of the tangential spring stiffness to the radial spring stiffness falls within the range of 1 to 3. This ensures that the translational and / or rotational modes are not the most energetically favorable modes, or that their natural frequencies are sufficiently far from the natural frequencies of the bending mode (or at least one of them).

[0023] The ring structure should vibrate at a low amplitude, preferably in the range of 0.1 μm to 10 μm, such that the spring stiffness of the tangential and radial springs remains constant. This means that both the tangential and radial springs remain within the linear range. Within this range, the displacement is directly proportional to the displacing force, i.e., the spring stiffness is constant. The linearity of the spring elements in this case is also due to the separation of the tangential and radial springs. This separation allows the displacement occurring parallel to the substrate to be divided into radial and tangential portions in each direction, which can be absorbed by the corresponding springs. This prevents some of the spring elements from being displaced in their preferred direction, i.e., in a direction that deviates from the linear range with small displacements. This makes it easier to control vibrations from the ring structure.

[0024] The spring element can have an extension of less than 25% of the radius in the radial direction of the ring structure when at rest. This is also possible with separate configurations of tangential and radial springs. In particular, radial springs are narrow in the radial direction of the ring structure, for example, occupying only 10% or 5% of the radius of the ring structure. Since tangential springs allow for smaller displacements than radial springs, they can also be designed more compactly. This enables a compact suspension for the ring structure and allows for a compact design of the coupling device. In particular, this makes the coupling device very compact.

[0025] In this arrangement, the spring elements can be connected to the ring structure from the outside. This enables the installation space inside the ring structure to be left free, for example, for additional components having additional functionality. Since the space requirements (required space) of the spring elements are low, much space is not required in the area outside the ring structure. As a result, the coupling device can be designed in a compact manner and yet can have improved functionality.

[0026] Each spring element can also be designed such that the space available for the displacement of the tangential spring in the tangential direction is less than half of the space available for the displacement of the radial spring in the radial direction. As described above, vibrations from the ring structure such that the part moving in the tangential direction of the ring structure is at most half of the part moving in the radial direction should be energetically preferred. Thus, the installation space that must be left free for the movement in the tangential direction can be reduced, and the freed-up installation space can be used for other components. Thereby, the coupling device becomes more compact and yet can be equipped with a large number of structural elements.

[0027] Electrodes for exciting and / or reading vibrations from the ring structure can be arranged between the spring elements in the circumferential direction of the ring structure when used as a ring gyroscope and generally. As a result, the ring structure becomes particularly compact in design.

[0028] Each electrode can extend in the circumferential direction over an angle between 10° and 45°, preferably between 15° and 30°, more preferably an angle of 18°, measured from the center of the ring structure, depending on the number of spring elements used. As a result, the electrodes contact a large continuous part (section) of the ring structure. Thereby, the voltage required for the electrodes to apply / read a force is reduced. Thereby, the operation of the coupling device becomes more efficient.

[0029] The spring elements are thought to be evenly distributed in the circumferential direction of the ring structure. This makes it easier to excite the ring structure uniformly.

[0030] Each spring element connects the ring structure to the substrate via precisely one anchor structure. This prevents so-called "anchor losses," which occur when forces are introduced to the substrate through multiple points and can only be balanced at the substrate level. "Anchor losses" refer to the energy lost when forces and torques at the anchor are introduced to the substrate and then dissipate into the environment through the substrate. This can be counteracted by balancing the forces and torques and transmitting these forces and torques to the substrate at the least central point possible. Therefore, by using only one anchor structure, the occurrence of such anchor losses is reduced.

[0031] In each spring element, the radial spring may have a double-folded bent beam spring that extends tangentially and is radially connected to the substrate and the tangential spring, and the tangential spring may be a bent beam spring with more folds than double-folded, or may include at least two double-folded bent beam springs that extend radially and are radially connected to the radial spring and the ring structure. As a result, spring elements corresponding to the above can be manufactured in a simple manner.

[0032] A ring gyroscope can include a micro-mechanical coupling device as described above. In this case, the ring structure is suitable for generating excited vibrations, which are superimposed on detected vibrations generated by the Coriolis force during the rotation of the ring structure. The spring element in this case constitutes a micro-mechanical component. In this way, a ring gyroscope can be achieved in which undesirable translational modes or their natural frequencies can be sufficiently isolated from the desired operating modes or their frequencies.

[0033] The so-called "angular gain" of the second natural vibration from the ring structure (which is formed from the ratio of the Coriolis mass to twice the modal mass) can be in the range of 0.3 to 0.4, preferably between 0.35 and 0.4, and more preferably between 0.38 and 0.4 (the endpoints are part of the specified range). In this case, the modal mass represents the proportional mass of the associated natural vibration, i.e., the effective mass of the corresponding natural vibration. It is derived from the eigenvector and mass distribution of the corresponding mode. The Coriolis mass consists of all mass points that move in the direction of the excited vibration during excited vibration and in the direction of the detected vibration during detection. The so-called "angular gain" can be determined from the ratio of the Coriolis mass to the modal mass. The theoretical maximum angular gain is 1 (Foucault pendulum). A large angular gain is favorable and can be understood as the gain coefficient of the angular velocity signal. Theoretically, the angular gain of a ring gyroscope with n=2 natural modes is 0.4. The coupling device described above, which operates as a ring gyroscope, can achieve an angular gain very close to this theoretical value. [Brief explanation of the drawing]

[0034] The present invention will be described in further detail with reference to the following drawings. The following description is illustrative and should not be construed as limiting. The present invention is defined solely by the subject matter of the claims.

[0035] [Figure 1A] A schematic diagram of a micro-electromechanical coupling device is shown. [Figure 1B] A schematic diagram of a micro-electromechanical coupling device is shown. [Figure 2] A schematic diagram of a spring element formed from a combination of tangential and radial springs is shown. [Figure 3A] Figure 2 shows schematic diagrams of the displacements of radial and tangential springs. [Figure 3B] Figure 2 shows schematic diagrams of the displacements of radial and tangential springs. [Figure 4] A schematic diagram of another spring element is shown. [Figure 5] A schematic diagram of another spring element is shown. [Figure 6] A schematic diagram of another spring element is shown. [Figure 7] A schematic diagram of another spring element is shown. [Figure 8] A schematic diagram of another spring element is shown. [Figure 9] A schematic diagram of a ring gyroscope constructed from a micro-electromechanical coupling device is shown. [Figure 10] A schematic diagram of another ring gyroscope is shown. [Figure 11] A schematic diagram of the arrangement of electrodes and spring elements within the coupling device is shown. [Modes for carrying out the invention]

[0036] Figures 1A and 1B show schematic diagrams of a micro-electromechanical coupling device 100 suitable for coupling micro-electromechanical components, such as those used as micro-electromechanical measuring devices, including, for example, angular velocity sensors and / or acceleration sensors. The micro-electromechanical coupling device 100 can also form the basic structure of an annular angular velocity sensor. Figure 1B is a cross-sectional view along line II in Figure 1A.

[0037] The coupling device 100 comprises a flexible ring structure 110 and a plurality of spring elements 120. As shown in Figure 1A, the ring structure forms a circle when at rest and is deformable substantially parallel to the plane of the circle. As shown in Figure 1B, the ring structure 110 has a substantially rectangular cross-section perpendicular to the plane of the circle or perpendicular to the substrate 200 on which the ring structure 110 is mounted. The longer side of this substantially rectangle perpendicular to the substrate 200 is many times longer than the shorter side parallel to the substrate 200. Therefore, the ring structure 110 can be considered, for example, a self-contained bending beam spring that is deformable parallel to the substrate 200, and deformation perpendicular to the substrate 200 can be ignored (in the first approximation). The shape of the ring structure 110 shown is purely illustrative. The ring structure 110 can have any shape that allows deformation substantially parallel to the substrate plane only. The ring structure 110 may also have a degenerate circular shape when at rest, and can be designed, for example, as an ellipse or a polygon with rounded corners. Therefore, such degenerate circular shapes are also intended to be covered by reference to the circular ring structure 110.

[0038] The coupling point 112 is shown on the ring structure 110, at which the coupled micro-electromechanical components act, or these components are connected to the ring structure 110. This coupling allows for the transmission or regulation of motion between the micro-electromechanical components. In particular, the coupling device 100 can mediate force and torque-free push-pull vibrations between components. Micro-electromechanical components are, for example, sensor masses or vibration systems. However, in principle, the type, structure, and size of the coupled components 200 are arbitrary. The number of components 200 may be more than two.

[0039] This coupling can also be exerted via a spring element 120. In this case, the coupling point 112 does not exist. In particular, if the coupling device 100 is part of an annular micro-electromechanical angular velocity sensor such as a ring gyroscope, the spring element 120 may constitute a micro-electromechanical component. In this case, the ring structure is suitable for generating an excitation vibration that is superimposed on the detection vibration generated by the Coriolis force during the rotation of the ring structure 110.

[0040] The ring structure 110 is connected to the substrate 200 via a plurality of spring elements 120. The spring elements 120 act on various points of the ring structure 110, holding it on the substrate 200. As shown in Figures 1A and 1B, the spring elements 120 can be connected to an anchor structure 125, thereby directly connecting the ring structure 110 to the substrate 200. In this configuration, the anchor structure 125 can have any shape, as long as it can be fixedly connected to the substrate 200.

[0041] As schematically shown in the enlarged view of Figure 1A, each spring element 120 has at least one tangential spring 122 that can be displaced substantially tangentially with respect to the ring structure 110, and at least one radial spring 124 that can be displaced substantially radially with respect to the ring structure 110.

[0042] The tangential spring 122 and radial spring 124 are fully schematicly represented in Figure 1A by the symbol for a coil spring. The tangential spring 122 and radial spring 124 of each spring element 120 are independent components, and the ratio of the spring stiffness of the tangential spring 122 to the radial spring 124 of each spring element 120 is configured such that the vibration that deforms the ring structure 110 is energetically more favorable than the vibration that translationally displaces the ring structure 110 relative to the substrate 200, and / or the natural frequency of the translational vibration and the nearest natural frequency of the deformation vibration are located at a distance of more than 5% of the natural frequency of the deformation vibration. Preferably, the distance between natural frequencies is in the range of 5% to 200% of the natural frequency of the deformation vibration, more preferably 5% to 100%, and even more preferably 5% to 50%.

[0043] Therefore, the spring element 120 is composed of springs that are substantially independently deformable, and the overall motion / deformation of the spring element 120 is divided into a radial component and a tangential component by generating a radial component through the deformation of the radial spring 124 and a tangential component through the deformation of the tangential spring 122. In this configuration, the tangential spring 122 and the radial spring 124 are separate assemblies, and their dimensions and characteristics can be set separately during the manufacturing process of the coupling device 100. In particular, the mass and thickness of the tangential spring 122 and the radial spring 124 can be designed differently to achieve different spring stiffnesses, for example, in the etching process.

[0044] In this way, the ratio of the spring stiffness of the tangential spring 122 to the radial spring 124 can be set such that translational or rotational vibrations from the ring structure 110, i.e., vibrations that do not deform the ring structure 110, are energetically less favorable than vibrations that deform the ring structure 110. Preferably, a second natural vibration from the freely floating ring structure 110, i.e., an n=2 natural mode in which two wave antinodes are formed, should be energetically more favorable than the translational or translational mode and / or rotational mode by the connection to the spring element 120. The ratio of the spring stiffness in the individual spring elements 120 can also be set such that the natural modes of the freely floating ring structure 110 are rearranged, i.e., for example, the n=3 natural mode of the freely floating ring structure 110 is energetically more favorable than the n=2 natural mode by the coupling to the spring element 120. For this purpose, the ratio of the spring stiffness in the individual spring elements 120 can also be configured differently.

[0045] Instead of achieving (or in addition to) reallocating the excitation energy of the individual natural modes of the freely floating ring structure 110, the ratio of the spring stiffness of the tangential spring 122 to the radial spring 124 can also be set such that the natural frequencies of the natural modes are sufficiently far apart from each other. In particular, the natural frequencies of the translational and / or rotational modes should be sufficiently far from the initial natural frequencies of the bending modes that deform the ring structure 110, and it should be ensured that the influence of the force that excites the translational modes does not couple to and interfere with these bending modes. For this purpose, the natural frequencies may be spaced, for example, more than 5% of the natural frequency of the bending mode. Preferably, the distance between natural frequencies is in the range of 5% to 200%, more preferably 5% to 100%, and even more preferably 5% to 50% of the natural frequency of the deformation vibration.

[0046] The spring element 120 can be designed such that the ratio of the spring stiffness of the tangential spring 122 to the spring stiffness of the radial spring 124 falls within the range of 1 to 3. If the spring stiffness of the tangential spring 122 is selected to be greater than that of the radial spring 124, the tangential motion is suppressed. This favors motion patterns where the maximum tangential displacement is smaller than the maximum radial displacement, such as n=2 eigenmodes.

[0047] For the same reason, each spring element 120 can also be designed such that the space available for the displacement of the tangential spring 122 in the tangential direction is less than half the space available for the displacement of the radial spring 124 in the radial direction. On the one hand, this suppresses the translational mode itself. On the other hand, if the spring elements 120 are set up accordingly, the tangential space is not required and can be used for the placement of other components such as electrodes.

[0048] In particular, the ring structure 110 should vibrate with a low amplitude, preferably in the range of 0.1 μm to 10 μm, such that the spring stiffness of the tangential spring 122 and the radial spring 124 remains constant. Therefore, the spring element 120 behaves like a linear spring within the displacement range of the ring structure 110. The linearity of the spring element 120 in this case is also due to the separation of the tangential spring 122 and the radial spring 124. This separation allows the displacement occurring parallel to the substrate 200 to be divided into a radial portion and a tangential portion in each direction, and absorbed by the corresponding springs. This prevents a part of the spring element 120 from being displaced in its preferred direction, i.e., in a direction that deviates from the range of linearity with a small displacement. This makes it easier to control vibrations from the ring structure 110.

[0049] The above coupling device configuration makes it possible to effectively suppress the excitation of the translational mode compared to the excitation of the bending mode. By separating the spring element 120 into a tangential spring 122 and a radial spring 124, a more compact design of the spring element 120 becomes possible, and as a result, a compact design of the coupling device 100 and suppression of the translational mode can be achieved.

[0050] The spring element 120 can have an extension of less than 25% of the radius in the radial direction of the ring structure 110 when stationary, which makes the coupling device 100 particularly compact. This makes it possible to place additional components within or around the ring structure 110.

[0051] The spring element 120 can be connected to the ring structure 110 from the inside, as shown in Figure 1A. Due to its compact design, most of the interior of the ring structure 110 remains empty. However, because these small sizes do not lead to an excessively large coupling device, the spring element can also be connected to the ring structure 110 from the outside. This allows for configurations that leave the interior of the ring structure 110 completely empty for the placement of additional components, which is not possible in state-of-the-art designs where the ring structure is held by a long, centrally fixed spring or a large frame structure.

[0052] In principle, as shown in Figure 1A, the spring elements 120 can be irregularly distributed along the ring structure 110 if it is advantageous for suppressing the intended translational modes. However, for ease of manufacturing, it is preferable that the spring elements be evenly distributed in the circumferential direction of the ring structure 110. Furthermore, this facilitates uniform excitation of the ring structure 110.

[0053] As shown in Figures 1A and 1B, each spring element 120 connects the ring structure 110 to the substrate 200 via exactly one anchor structure 125. This reduces the damping mechanism of so-called "anchor loss," which occurs when forces are introduced to the substrate through multiple points and they can only be balanced at the substrate level. Anchor loss refers to the energy lost as a result of forces and torques introduced to the substrate by the anchor and dissipated into the environment through the substrate. This can be counteracted by balancing the forces and torques and transmitting these forces and torques to the substrate at as few and as central a point as possible. Therefore, by using only one anchor structure, the occurrence of such anchor loss is reduced.

[0054] As shown in Figure 1A, the coupling device 110 may have multiple spring elements 120. However, the number of spring elements 120 may vary. For example, 4, 8, 16, 24, or 32 spring elements 120 may be used.

[0055] Figures 2-8 show different embodiments of the spring element 120. Common to these different embodiments is that the spring element 120 has a radial spring 124 which is a double-folded bent beam spring that extends tangentially and is radially connected to the substrate 200 and the tangential spring 122, and the tangential spring 122 which is a bent beam spring with more folds than double-folded, or includes at least two double-folded bent beam springs that extend radially and are radially connected to the radial spring 124 and the ring structure 110. In principle, other configurations are of course possible as long as the tangential spring 122 and the radial spring 124 can be characterized separately. For example, the radial spring 124 may be attached to the ring structure and the tangential spring 122 may be attached to the substrate 200.

[0056] Figure 2 shows a spring element 120 in which the radial spring 124 is designed as a double folded bent beam spring that establishes a connection between the anchor point 125 and the tangential spring 122. This means that the bent beam extending tangentially is connected to the anchor structure 125, preferably at its center. At each end, the bent beam is folded back 360°, i.e., running parallel to itself, thereby forming a second bent beam running parallel to the first bent beam. The two bent beams are connected at their ends. Such a structure can be manufactured by an etching process in a manner known to itself.

[0057] The tangential spring 122 consists of a bent beam spring that runs radially from a connection point (preferably located centrally) with the radial spring 124 to the ring structure 110. A double-folded bent beam spring, which is folded back itself to run in a meandering pattern, is connected to the end of this bent beam spring. In this configuration, the long side of the meander runs parallel to the centrally located bent beam spring, i.e., radially. In the example in Figure 2, there are three meanders, and the connection between the radial spring 124 and the ring structure 110 is at the central point. However, there may be other numbers of meanders.

[0058] The displacement of this spring element 120 is shown in a greatly exaggerated manner in Figures 3A and 3B. Figure 3A shows the displacement in the radial direction r, in which case substantially only the radial spring 124 deforms. Figure 3B shows the displacement in the tangential direction t, in which case substantially only the tangential spring 122 deforms.

[0059] The spring stiffness of the springs can be set independently of each other by appropriately selecting the dimensions of the bent beam springs that form the tangential spring 122 and the radial spring 124, for example, by selecting etching parameters during manufacturing. Furthermore, the spring element 120 shown in Figure 2 is very compact. Therefore, by using it in the coupling device 100 described above, translational modes can be suppressed without using excessive installation space.

[0060] The spring element 120 shown in Figure 4 corresponds to the design in Figure 2, except that it uses two double-folded bent beam springs for the radial spring 124. This allows for more flexible setting of the parameters of the radial spring 124.

[0061] The spring element 120 shown in Figure 5 uses a pair of bent beam springs arranged in a fork shape as the tangential spring 122, i.e., a pair of bent beam springs connected at one end and interconnected at the other end. This design also allows the spring parameters of the tangential spring 122 and the radial spring 124 to be set independently of each other.

[0062] Figures 6 and 7 show two variations of the "bifurcated bent beam fork," which is connected to a radial spring 124 or a ring structure 110 via a single bent beam. These designs are particularly compact in the tangential direction.

[0063] Figure 8 shows a modified example in which the tangential spring 122 consists of two double-folded bent beam springs connected to the radial spring 124 by a frame, and a bent beam spring fixed to the ring structure 110. Furthermore, the radial spring 124, designed as a double-folded bent beam spring, is not continuous but merges with the frame.

[0064] Examples from Figures 2 to 8 demonstrate that there are a wide variety of different configurations of the spring element 120, allowing for free adjustment of the ratio of spring stiffness between the tangential spring 122 and the radial spring 124 within the range of manufacturing conditions in order to suppress translational modes.

[0065] Figure 9 shows a coupling device 100 in which the coupled microelectromechanical component is a spring element 120. This means that the coupling device 100 corresponds to a deformable ring attached to the spring on a substrate 200. This ring can be used as a ring gyroscope 300 because the ring structure 110 is suitable for generating excited vibrations that are superimposed on the detected vibrations generated by the Coriolis force during the rotation of the ring structure 110. Thus, if the ring structure 110 is set to an oscillating state, for example by using an excitation electrode, the rotation of the ring structure 110 leads to a change in this vibration, which can be read out, for example, via a detection electrode, and from there the angular velocity of the rotation can be determined.

[0066] Here, suppressing the translational mode, or separating the natural frequency of the translational mode from the operating frequency / excitation frequency of the ring gyroscope 300, is particularly advantageous because it reduces interference with the measurement. This improves the measurement accuracy of the ring gyroscope 300.

[0067] As shown in Figure 10, for example, to increase the mass of the oscillating ring structure 110, multiple concentric rings connected to each other by short springs, such as short radially bent beams or webs, can also be used as the ring structure 110 of the ring gyroscope 300.

[0068] As can be seen in Figures 9 and 10, the spring element 120 is compactly designed compared to the dimensions of the ring structure 110 (less than 1 / 4 of the radius), and therefore does not significantly increase the installation space of the ring gyroscope 300 compared to the ring structure 110 without the spring element 120.

[0069] The electrodes 140 for exciting and / or reading vibrations from the ring structure 110 can be positioned between the spring elements 120 in the circumferential direction of the ring structure 110, both when used as a ring gyroscope 300 and generally. This is illustrated in Figure 11. In this way, vibrations from the ring structure 110 can be excited or measured in a compact manner. Furthermore, the electrodes 140 can almost completely surround the ring structure 110 in the circumferential direction, thereby achieving homogeneous response behavior from the ring structure 110.

[0070] As shown in Figure 11, the electrode 140 can be moved relatively close to the tangential spring 122 because they displace relatively little due to the suppressed translational modes. This improves the interaction between the electrode 140 and the ring structure 110, and therefore improves the response behavior from the ring structure 110. In addition, the voltage required for the electrode to apply / read out force is reduced.

[0071] Each electrode 140 can extend circumferentially over an angle between 10° and 45°, measured from the center of the ring structure 110, depending on the number of spring elements 120 used. When using 10 to 20 spring elements 120, an angular range between 15° and 30° has been proven preferable. For example, 16 spring elements 120 can be used, evenly distributed circumferentially along the ring structure 110, with each electrode 140 occupying an angle of 18°. In this way, electrodes 140 can be placed over 80% of the circumferential circumference of the ring structure 110. Generally, placing electrodes 140 in the range of 70% to 90% of the circumferential circumference of the ring structure 110 is considered advantageous for the response behavior from the ring structure 110.

[0072] In the ring gyroscope 300, the angular gain (ratio of Coriolis mass to twice the modal mass) of the second natural oscillation from the ring structure 110, i.e., the n=2 natural mode, can be in the range of 0.3 to 0.4, preferably in the range of 0.35 to 0.4, and more preferably in the range of 0.38 to 0.4 (including the endpoints).

[0073] In this case, the modal mass represents the proportional mass of the associated natural vibration, i.e., the effective mass of the corresponding natural vibration. It is derived from the eigenvector and mass distribution of the corresponding mode. The Coriolis mass consists of all mass points that move in the direction of the excited vibration during excited vibration and in the direction of the detected vibration during detection. The so-called "angular gain" can be determined from the ratio of the Coriolis mass to the modal mass. The theoretical maximum angular gain is 1 (Foucault pendulum). A large angular gain is favorable and can be understood as the gain coefficient of the angular velocity signal. Theoretically, the angular gain of a ring gyroscope with n=2 eigenmodes is 0.4. According to the coupling device 100 described above, which operates as a ring gyroscope 300, an angle very close to this theoretical value can be achieved. This is thought to be due to the suppression of translational modes.

Claims

1. A micro-electromechanical coupling device (100) for connecting micro-electromechanical components, A flexible ring structure (110) that forms a circle when stationary, is substantially deformable parallel to the plane of the circle, and is suitable for connecting the micro-electromechanical components, The ring structure (110) has a plurality of spring elements (120) suitable for connecting to a substrate (200), Each spring element (120) is, The ring structure (110) is provided with at least one tangential spring (122) that is substantially displaceable tangentially to the ring structure (110), The ring structure (110) has at least one radial spring (124) that is substantially displaceable in the radial direction, The tangential spring (122) and radial spring (124) of each spring element (120) are independent components. A micro electromechanical coupling device (100) characterized in that the ratio of the spring stiffness of the tangential spring (122) and the radial spring (124) of each spring element (120) is configured such that the vibration that deforms the ring structure (110) is energetically more advantageous than the vibration that displaces the ring structure (110) with respect to the substrate (200) in translation and / or rotation, and / or the natural frequency of the translation and / or rotation vibration and the nearest natural frequency of the deformation vibration are separated by more than 5% of the natural frequency of the deformation vibration.

2. The coupling device (100) according to claim 1, characterized in that the spring element (120) is designed such that the ratio of the spring stiffness of the tangential spring (122) to the spring stiffness of the radial spring (124) falls within the range of 1 to 3.

3. The coupling device (100) according to claim 1 or 2, characterized in that the ring structure (110) is suitable for exciting the tangential spring (122) and the radial spring (124) to vibrate at an amplitude such that the spring stiffness of the tangential spring (122) and the radial spring (124) is kept constant, preferably in the range of 0.1 μm to 10 μm.

4. The coupling device (100) according to any one of claims 1 to 3, characterized in that the spring element (120) has a radial spread of less than 25% of the radius of the ring structure (110) when stationary.

5. The coupling device (100) according to any one of claims 1 to 4, characterized in that the spring element (120) is connected to the ring structure (110) from the outside.

6. The coupling device (100) according to any one of claims 1 to 5, characterized in that each spring element (120) is designed such that the space available for the displacement of the tangential spring (122) in the tangential direction is less than half the space available for the displacement of the radial spring (124) in the radial direction.

7. The coupling device (100) according to any one of claims 1 to 6, characterized in that an electrode (140) for exciting and / or reading vibrations from the ring structure (110) is arranged between the spring elements (120) in the circumferential direction of the ring structure.

8. The coupling device (100) according to claim 7, characterized in that each of the electrodes (140) extends circumferentially over an angle between 10° and 45°, preferably between 15° and 30°, and more preferably between 18°, measured from the center of the ring structure (110).

9. The coupling device (100) according to any one of claims 1 to 8, characterized in that the spring element (120) is evenly distributed in the circumferential direction of the ring structure (110).

10. The coupling device (100) according to any one of claims 1 to 9, characterized in that each spring element (120) connects the ring structure (110) to the substrate (200) via a single anchor structure.

11. In each spring element (120), The radial spring (124) It has a double folded-bend beam spring that extends tangentially and is radially connected to the substrate (200) and the tangential spring (122), The coupling device (100) according to any one of claims 1 to 10, characterized in that the tangential spring (122) is a bent beam spring that is folded more than a double fold, or includes at least two double-folded bent beam springs that extend radially and are radially connected to the radial spring (124) and the ring structure (110).

12. A ring gyroscope (300) comprising a micro electromechanical coupling device (100) according to any one of claims 1 to 11, The ring structure (110) is suitable for generating excitation vibrations that are superimposed on the detection vibrations generated by the Coriolis force during the rotation of the ring structure (110). The ring gyroscope (300) is characterized in that the spring element (120) constitutes the micro-electromechanical component.

13. The ring gyroscope (300) according to claim 12, characterized in that the angular gain of the second natural vibration from the ring structure (110), i.e., the ratio of Coriolis mass to twice the modal mass, is in the range of 0.3 to 0.4, preferably in the range of 0.35 to 0.4, more preferably in the range of 0.38 to 0.4, and the endpoints are part of the specified range.

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