Mechanical-electrical generator

Abstract

A mechanical-electrical generator is described with a base, an oscillating pendulum which is connected to the base in such a way that the oscillating pendulum can execute a torsional oscillation with respect to the base in response to a vibration of the mechanical-electrical generator, a stop device which is coupled to the oscillating pendulum and the base in such a way that a complete torsional oscillation is prevented, and the stop device is designed to exert an elastic stop effect on the oscillating pendulum when the oscillating pendulum and the stop device interact, an energy converter device which is designed to convert the torsional oscillation of the oscillating pendulum into an electrical signal, and with an electrical output for coupling out the electrical signal to which a load can be coupled.

Description

[0001] The present invention relates to a mechanical energy converter, in particular to a mechanical-electrical generator.

[0002] In recent years, both the demand and the possible application scenarios for small, mobile, and / or autonomous systems have increased significantly. With this demand and interest, efforts in the development of wireless sensor and actuator networks have also increased. The potential applications for such networks are diverse. They can be used in the automotive sector, medical technology, building surveillance, chemical detection, military applications, and other areas. However, due to the lack of cable connections to other components, these systems require a decentralized energy supply. Energy supply systems that enable energy harvesting from the local environment represent an extremely promising concept for replacing exhaustible energy storage devices, such as batteries, accumulators, or fuel tanks with corresponding fuel cells.For several years now, research has focused in particular on the conversion of kinetic energy into electrical energy.

[0003] Miniaturized vibration generators are generally designed as spring-mass-damper systems. The conversion of the kinetic energy, which is made available externally to such a spring-mass-damper system in the form of movement, usually occurs through inductive conversion, with the system being designed so that the inertial mass of the system is embodied as a permanent magnet. If the system is then excited by vibrations, the resulting relative movement of the permanent magnet with respect to a coil connected to the rest of the system leads to an induced voltage. The induced current caused by the induced voltage, in turn, builds up a magnetic field in the coil that counteracts the movement of the permanent magnet and thus dampens its movement. The energy dissipated in the damping corresponds, to a first approximation, to the electrically generated energy.As approximately linear error elements, i.e. as spring elements with a linear characteristic or a linear force-displacement characteristic, beams and membranes are used in addition to the classic spring, especially in microsystem technology.

[0004] Due to their design as systems with springs, a (flywheel) mass, and a damper, these systems are resonant systems with a characteristic resonance frequency or natural frequency. However, resonant systems have characteristic disadvantages. To generate the greatest possible power, the system should have the lowest possible damping. This means that the generator must then be excited relatively precisely at its resonance frequency or natural angular frequency in order to ensure a sufficiently large relative movement of the magnet with respect to the (induction) coil. Vibration sources that deliver a constant and known vibration frequency are generally very difficult to find. Technically, vibration sources whose vibration frequencies and vibration amplitudes are subject to temporal fluctuations are more prevalent.Even small deviations of the vibration from the resonance frequency of such a resonant system with weak damping lead to considerable losses in the power that can be generated by the generator.

[0005] In principle, it is possible to counteract this effect by increasing the damping of the spring-mass-damper system. However, with increasing damping, the maximum energy that can be generated also decreases, which is also unfavorable.

[0006] Furthermore, generators manufactured using microsystems technology exhibit comparatively high resonance frequencies or characteristic frequencies due to the low masses of the components manufactured using microsystems technology. This further exacerbates the above-described problem of matching the resonance frequencies of the spring-mass-damper systems to the vibration frequencies, since potential vibration sources generally oscillate at frequencies that are usually at least an order of magnitude lower than the resonance frequencies of generators that can be achieved using microsystems technology. This will be explained in more detail later in this application using the example of a vacuum pump.

[0007] Furthermore, vibration spectra typically show harmonics with significant energy in addition to the fundamental frequency. However, a resonant system can only convert kinetic energy around a specific frequency, namely the resonance frequency.

[0008] Furthermore, in the case of resonant energy conversion by a generator, a physical stop should be provided to protect the spring from overload. If the magnets continuously oscillate against this stop, this will also lead to material failure sooner or later, which generally significantly reduces the service life of the generator.

[0009] Most resonant vibration generators use spring elements that exhibit approximately linear behavior, i.e., a linear characteristic. However, there is also the approach of using the repulsive force of two oppositely polarized magnets as a non-linear spring force. Fig. 4 shows a magnetic translation system 800 with a sleeve 810, an oscillating magnet 820 and two spring magnets 830-1, 830-2, which are mechanically connected to the sleeve 810 and aligned such that inside the sleeve 810, a north pole of the oscillating magnet 820 is opposite a north pole of the spring magnet 830-1 and a south pole of the oscillating magnet 820 is opposite a south pole of the spring magnet 830-2. To simplify the illustration, Fig. 4 an induction coil of the magnetic translation system 800 is not shown, which can be connected, for example, to the sleeve 810 and can provide an induction voltage in response to a movement of the oscillating magnet 820.

[0010] As described and explained in the dissertation entitled “Energy converter system for the operation of autonomous sensors in vehicles” by Gunther Naumann (Technical University of Dresden, 2004), it is especially with oscillating magnets, such as the oscillating magnet 820 in Fig. 4, with a linear guide inside the sleeve 810, high frictional forces of the oscillating magnet 820 on the sleeve 810 result due to a tilting moment generated by the orientation of the two spring magnets 830-1, 830-2 and the oscillating magnet 820 relative to one another. Due to the high frictional forces caused by the tilting moment, a linear guide of the oscillating magnet 820 in the sleeve 810 has so far led to high losses.

[0011] More precisely, due to the mutual repulsion of the north poles of the oscillating magnet 820 and the spring magnet 830-1 and the south poles of the oscillating magnet 820 and the spring magnet 830-2, a tilting moment occurs which the two spring magnets 830-1, 830-2 exert on the oscillating magnet 820, so that the latter is tilted by an angle β relative to the sleeve 810 or a rotation axis of the sleeve.

[0012] Due to the tilting moment, not only a normal force F Nbetween the sleeve 810 and the oscillating magnet 820, as shown at a point A in Fig. 4, on the sleeve 810 or the oscillating magnet 820, but additionally a magnetic force component F MR between the oscillating magnet 820 and the sleeve 810. Due to the additional magnetic force component F MK there is an increase in a friction force F R , which the sleeve 810 exerts on the oscillating magnet 820, compared to the case where the magnetic force component F MK for example, would be less or disappear completely due to weaker magnets.

[0013] In case of movement of the oscillating magnet 820 relative to the sleeve 810, the friction force F R to a power loss, so that the energy that a generator with the magnetic translation system 800 could produce is reduced. The friction force F RHowever, it also occurs in a stationary state where the oscillating magnet 820 is not moving. In this case, the friction force F R by a static friction force which, together with the forces exerted by the two spring magnets 830-1, 830-2 on the oscillating magnet 820, corresponds to a gravitational force F g of the oscillating magnet 820. When using a magnetic spring in the form of the two spring magnets 830-1, 830-2 and the oscillating magnet 820 as well as a linear guide in the form of the sleeve 810, additional frictional forces arise which are caused by a rotation of the oscillating magnet 820 relative to the sleeve 810 or the axis of symmetry of the sleeve 810.

[0014] Other examples of generators with translational energy conversion systems are shown in US Pat. Nos. 534,786 A, 4,140,932 A, and DE 197 58 164 A1. Furthermore, US Pat. No. 5,148,066 A shows a linear generator or motor with an integrated magnetic spring, in which the magnetic system performs bearing and guiding functions. US Pat. No. 6,867,520 B2 also shows an electromechanical battery in the form of a magnetically suspended flywheel.

[0015] The above-cited dissertation by Gunther Naumann also contains an introduction to the basic structure and properties of rotating energy conversion systems.

[0016] Fig. 5 shows a vibration transducer 850 with a body 860 into which several coils 870 are embedded, and which is described in the conference paper "Novel non-resonant vibration transducer for energy harvesting" from the Power Micro Electronic Mechanical Systems 2005 conference in Tokyo, Japan, by D. Spreemann, B. Folkmer, D. Mintenbeck, and Y. Manoli. The vibration transducer 850 also has a rotation pendulum 880 with two magnets 890. The rotation pendulum 880 has a teardrop shape and is connected to a shaft 900 at a suspension point such that the suspension point does not coincide with a center of gravity of the rotation pendulum 880. As a result, the rotation pendulum 880 hangs "down" in a rest state when the vibration transducer 850 is upright. The shaft 900 is rotatably connected to the body 860 via a ball bearing 910.

[0017] Now, as in Fig. 5 indicated by the two vertical arrows, the vibration transducer 850 is moved vertically, due to the shape of the rotation pendulum 880 and the suspension point, the rotation pendulum 880 begins a rotation about an axis that coincides with the shaft 900 in terms of its position. In Fig. In Figure 5, the rotation is indicated by an arrow in the area of ​​shaft 900. Due to the resulting rotation, magnets 890 are moved past coils 870, so that an induction voltage and thus an induction current are generated in coils 870 due to induction.

[0018] The rotatable mounting of the rotation pendulum 880 in the form of the shaft 900 and the ball bearing 910, as well as the drop-shaped design of the rotation pendulum 880 in conjunction with the suspension point, enable a non-resonant conversion of kinetic energy in the form of vibrations into electrical energy via the induced voltages and induced currents generated in the coils 870. This non-resonant conversion largely eliminates the disadvantages of a resonant conversion described above.

[0019] A disadvantage of the vibration converter 850, however, is that it relies on rotation, i.e., circling of the rotation pendulum 880 around the rotation axis determined by the position of the shaft 900, in order to efficiently provide electrical energy in the form of induced voltages. In other words, in order for the vibration converter 850 to deliver sufficient power, the rotation pendulum 880 must complete complete circles around the rotation axis. A particular disadvantage of this is that a vibration amplitude of the vibration converter must first exceed a critical value before the rotation pendulum 880 can even begin to rotate.If the amplitude of the vibrations does not exceed this critical value, the rotary pendulum 880 merely oscillates to maintain its rest position due to gravity, i.e., due to the mass distribution of the rotary pendulum 880 and the position of the attachment point of the shaft 900 in the rotary pendulum 880, which ultimately results in the vibration transducer 850 generally being unable to deliver sufficient electrical power. This is immediately apparent, since the amplitudes shown in . Fig. 5 are in this case exposed to only a comparatively small change in the magnetic flux due to the movement of the magnets 890.

[0020] US Patent No. 2,038,954 A shows a motor generator designed as a large pendulum-like device. The pendulum must be set into oscillation, for example, by muscle power or another device.

[0021] Based on this prior art, the object of the present invention is to provide a mechanical-electrical generator and a method for generating an electrical signal which enable a more efficient conversion of a mechanical vibration into an electrical signal.

[0022] This object is achieved by a mechanical-electrical vibration generator according to claim 1 or a method for generating an electrical signal according to claim 14.

[0023] The present invention is based on the finding that a more efficient generation of an electrical signal from a mechanical vibration can be achieved by, on the one hand, connecting a swinging pendulum to a base in such a way that the swinging pendulum can execute a torsional oscillation with respect to the base in response to a vibration of the mechanical-electrical generator, and by coupling the swinging pendulum and the base to a stop device in such a way that a complete torsional oscillation is prevented and, at the same time, the stop device exerts an elastic stop effect on the swinging pendulum when the swinging pendulum and the stop device interact with each other. Via an additional energy converter device, the torsional oscillation of the swinging pendulum is converted into an electrical signal, which is then provided at an electrical output.

[0024] In the context of the present application, an elastic or partially elastic impact effect is understood to mean an interaction in which typically less than 50% and preferably less than 20% of the kinetic energy of the oscillating pendulum is not converted into potential energy. In other words, in the context of the present application, an elastic or partially elastic impact effect is understood to mean an interaction in which typically less than 50% and preferably less than 20% of the kinetic energy is "destroyed," i.e., converted into heat, plastic deformation, or another form of energy that is technically impossible or difficult to further utilize.

[0025] A further advantage is that the stop device can be designed to exhibit a non-linear characteristic. In particular, this makes it possible to initially exert a comparatively low restoring force on the oscillating pendulum for deflection angles in the range of the equilibrium angle of the oscillating pendulum of the mechanical-electrical generator, with the restoring force increasing significantly for larger deflection angles.

[0026] This can be achieved, for example, by using magnets or electrostatic systems within the anchorage device. A major advantage of non-linear magnetic fields or electrostatic fields is that the initially flat characteristic curve of the magnetic or electrostatic interaction can be exploited to convert small vibration frequencies into an electrical signal, even with a small volume of the mechanical-electrical generator.

[0027] A further advantage is that the stop device, for example in the form of spring magnets or corresponding electrostatic components, can be designed such that the interaction of the oscillating pendulum with the base is adjustable. This allows, for example, a mechanical-electrical generator according to the invention to be designed so that it can be explicitly adapted to specific operating conditions.

[0028] This can also be done during operation, for example, to optimize the output power. For example, if the spring magnets or the corresponding electrostatic components are mounted and arranged in such a way that they are adjustable relative to each other, the non-linear characteristic of the anchor device can be further utilized to better adapt the generator to the respective operating conditions.

[0029] Furthermore, due to the non-linear characteristic of the stop device in relation to the interaction with the oscillating pendulum, even low-frequency vibrations that would otherwise be technically difficult to utilize and control can be utilized. In particular, this results in the advantage that the mechanical-electrical generator can be used not only for vibration frequencies close to a resonant frequency, but ideally for all frequencies, i.e. in particular for the frequently high-energy harmonics of oscillations and vibrations. Furthermore, this results in an adjustable vibration generator that can also utilize stochastically occurring shocks. The mechanical-electrical generator according to the invention is therefore particularly suitable for converting stochastic shocks and low frequencies of typically less than 125 Hz and preferably less than 75 Hz, which are not precisely predetermined and known, into electrical signals.

[0030] In the case of the use of a stop device operating on magnets, in which the oscillating pendulum comprises an oscillating magnet, this can be used as an additional weight for the oscillating pendulum in order to shift a resonance frequency present in all mechanical systems further into the ranges of lower and thus technically relevant vibration frequencies.

[0031] A further significant advantage of the present invention is that by using an oscillating pendulum, in comparison to a translational energy converter system as described in the introductory sections of the present application, not only vibrations with respect to one spatial direction can be converted into electrical signals, but that due to the design of an oscillating pendulum, vibrations with respect to two spatial directions, i.e. vibrations in one plane, can be utilized.

[0032] Preferred embodiments of the present invention are explained in more detail below with reference to the accompanying drawings. Fig. 1a is a schematic overview drawing of a first embodiment of a mechanical-electrical generator according to the invention; Fig. 1b is a partial exploded view of the first embodiment of a mechanical-electrical generator according to the invention; Fig. 2 an example of a vibration spectrum of a vacuum pump at different areas of the housing of the vacuum pump; Fig. 3 shows a second embodiment of a mechanical-electrical generator according to the invention in the form of a micromechanical system; Fig. 4 a magnetic translation system according to the state of the art; and Fig. 5 a vibration transducer according to the state of the art.

[0033] With reference to the Fig. 1 to 3 will now describe a first embodiment of a mechanical-electrical generator according to the invention. Fig. 1 to 3, similar reference symbols are used for objects with similar functional properties.

[0034] Fig. 1a shows an overview of an adjustable, precision-mechanical vibration generator for the inductive conversion of kinetic energy in the form of vibrations and stochastic shocks 100 as a first embodiment of a mechanical-electrical generator according to the invention. Fig. 1b shows a partially exploded view of a section through the Fig. 1a shown vibration generator 100 according to the invention. The vibration generator 100 is described with reference to Fig. 1a and Fig. 1b is explained and described in more detail.

[0035] The vibration generator 100 thus has a base or a housing 110, which in the Fig. 1, is constructed in three parts. The parts of the housing 110 are connected to one another via four combinations of screws 120 and nuts 130. A ball bearing 150 is fitted into the housing 110 for the rotatable mounting of an oscillating pendulum 140, which is connected to a shaft 160. The shaft 160 is also connected to the oscillating pendulum 140. The housing 110 has a corresponding recess 170 in each of its three parts, which enables the oscillating pendulum 140 to execute a corresponding torsional oscillation within the housing 110 with respect to a rotational axis determined by the shaft 160. The oscillating pendulum 140 also has an oscillating magnet 180, which in the case of the Fig. 1 is cylindrical in shape.

[0036] Furthermore, the housing 110 has two further recesses 190, which are at least partially threaded. A grub screw 200, which in turn is connected to a field magnet 210, can be screwed into the threads of the recess 190 into the housing 110. In particular, the two grub screws 200 enable individual positioning of the field magnets 210 with respect to the oscillating magnet 180, which is connected to the oscillating pendulum 140.

[0037] The two field magnets 210 are oriented relative to the oscillating magnet 180 such that a repulsive or repulsive force occurs between each of the two field magnets 210 and the oscillating magnet 180. In other words, the two field magnets 210 are oriented relative to the oscillating magnet 180 such that a north pole of the oscillating magnet 180 is also opposite a north pole of one of the two field magnets 210. Analogously, a south pole of the oscillating magnet 180 is also opposite a south pole of the other field magnet 210.

[0038] Furthermore, two induction coils 220 are integrated in the recess 170 of the housing 110, each having a bore, so that the oscillating magnet 180 can be at least partially immersed in the bores of the two induction coils 220.

[0039] The two coils are also connected to an electrical connection in the form of two contact pins 230, which, however, are shown in Fig. 1b is not shown. The electrical connection of the induction coils 220 and the contact pins 230 can be made in parallel or series, depending on the application scenario. Furthermore, regardless of whether the two induction coils 220 are connected in parallel or series, the two induction coils can be connected both parallel and antiparallel with respect to a winding orientation. The two induction coils 220 can therefore optionally have the same or opposite winding orientation. The two induction coils 220, together with the oscillating magnet 180 of the oscillating pendulum 140, thus form an energy conversion device with which the kinetic energy of a torsional oscillation performed by the oscillating pendulum 140 can be converted into an electrical signal.

[0040] In the Fig. In the embodiment of a mechanical-electrical generator 100 shown in Figure 1, which is more precisely a precision mechanical vibration generator 100, the stop device comprises the two field magnets 210 and the oscillating magnet 180. This design of the stop device offers, as already indicated above, several significant advantages.

[0041] A significant advantage is the fact that, due to the use of magnets, the impact effect has a non-linear characteristic curve, with a flat characteristic curve with low restoring forces initially present in the region around an equilibrium position of the oscillating pendulum 140. Together with the comparatively large mass of the oscillating pendulum 140, which results from the oscillating magnet 180, the resonant frequency of the oscillating pendulum 140 with respect to the housing 110 acting as the base is thus at comparatively low frequencies. This makes it possible to convert vibrations into electrical signals that occur at technologically relevant low frequencies of the vibration spectrum, while at the same time keeping the volume of the vibration generator 100 comparatively small.For large deflections of the oscillating pendulum 140, the spring force increases disproportionately due to the interaction of the field magnets 210 and the oscillating magnet 180 due to the non-linear characteristic curve, so that the oscillating magnet 180 and thus the oscillating pendulum 140 experience a certain "de-position damping." A physical stop, such as a mechanical stop made of rubber or plastic, is rarely used with a correct design of the vibration generator 100 and can therefore be completely eliminated.

[0042] Because a physical stop does not necessarily have to be implemented, the vibration generator 100 offers the further significant advantage that it is not only permanently not damaged by vibrations with a large vibration amplitude, but that the energy of these vibrations can be better converted into electrical signals and thus into electrical energy. This is due to the fact that a magnetic stop device, such as the one in Fig. 1, enables an elastic stop effect even at high deflection angles. In contrast to mechanical stops, for example in the form of rubber buffers, considerably less vibration energy is converted into technically barely usable forms of energy, such as heat or plastic deformation. Typically, less than 50% of the energy contained in the vibration is lost in technically barely usable forms of energy. Preferably, the stop device even allows less than 20% of the energy contained in the vibration to be "lost."

[0043] Another significant advantage of the vibration generator 100 as described in Fig. 1 is shown by way of example, is that the spring magnets 210 can be mounted in such a way that they are adjustable, so that the non-linear characteristic of the magnetic interaction between the field magnets 210 and the oscillating magnet 180 can be further utilized or optimized in order to be able to adapt the generator 100 to different operating conditions. Fig. 1, the two grub screws 200 thus represent an adjustment device that enables a user of the vibration generator 100 to adapt the characteristics of the vibration generator 100 to a wide variety of operating conditions, which represents a significant advantage and a novelty that has not been recognized until now.

[0044] The vibration generator 100 according to the invention or a mechanical-electrical generator 100 according to the invention thus differs from previous concepts essentially in the following points. Instead of a linear guide, as explained in the introductory sections of the present application, the oscillating magnet(s) 180 are rotatably mounted via an oscillating pendulum 140. The high friction losses normally occurring in linearly guided systems, which are attributable to tilting of the oscillating magnet, can thus be reduced due to the significantly lower rolling friction losses of the (miniature) ball bearing 150. This results in a system with extremely low mechanical damping, which significantly improves the achievable efficiency of the vibration generator 100.

[0045] Furthermore, since the magnets or the oscillating magnet 180 can penetrate into the (induction) coils 220 on a circular path, a larger magnetic flux change can be generated in the induction coils 220, which significantly increases the maximum voltage that can be generated at the contact pins 230 of the vibration generator 100 compared to a generator in which the oscillating magnet cannot penetrate into the coils.

[0046] Furthermore, the vibration generator 100 allows the user to actively adjust the positions of the spring magnets or the field magnet 210. To do so, the user of the generator 100 can adjust the two grub screws 200 accordingly. This allows the differential slope of the spring characteristic generated by the combination of the field magnets 210 and the oscillating magnet 180 to be influenced in such a way that the vibration generator 100 can be specifically adapted to the corresponding vibration frequencies of a vibration source.

[0047] The new properties described have already been confirmed by initial prototypes of the described precision-engineered vibration generator 100. For example, with an initial precision-engineered prototype of a vibration generator 100 according to the invention, also referred to as an LFTT (LFTT = Low Frequency Tunable Transducer), it has already been demonstrated that, through a wide variety of excitations, for example in the form of vibrations from a vacuum pump, shakers, and minor shocks, a processor of the type MSP 430 F 437 could be supplied with such a large amount of energy that it could alternately display the current time, the HSG logo of the Hahn-Schickard Society, and a measured temperature on a display. These tests were carried out, among other things, on a rotary vane vacuum pump, the vibration spectra of which were measured at various locations on the pump in Fig. 2 are shown.

[0048] More precisely, this shows Fig. 2 shows five vibration spectra plotted against a frequency, normalized to the acceleration due to gravity g. The vibration spectra were measured on a top side, a front side, a left side, a switch housing, and a flange of the rotary vane vacuum pump. Fig. 2 shows, the spectra at about 25 Hz, about 50 Hz and about 100 Hz show significant acceleration values, sometimes exceeding 0.35 g. In particular, Fig. 2 also shows that significant vibration contributions occur not only at a fundamental oscillation or fundamental frequency, but also at higher harmonics.

[0049] Furthermore, it is possible, for example, to use the same vibration generator 100 to successively adjust it to different application areas or different vibration sources. For example, by varying the arrangement or position of the field magnets 210 via the grub screws 200, it is possible to initially adapt the vibration generator 100 to the described vacuum pump, in order to then use it, for example, on a motor vehicle engine to generate an electrical voltage or an electrical current. Likewise, after further adjustment, the same vibration generator 100 can be used with a different vibration source to generate electrical energy.

[0050] Through further modeling, simulation, optimization and miniaturization of the precision mechanical generator, the power output of the vibration generator 100 can be further increased.

[0051] Deviating from the above-described embodiment of a vibration generator 100 according to the invention, a bearing other than the described ball bearing 150 can also be used. Instead of the described ball bearing 150, a different type of rolling bearing, such as a roller bearing or a needle bearing, can also be used. Likewise, a plain bearing can also be used, which, for example, comprises components made of a plastic (e.g., Teflon). ® ), a metal, or a metal alloy. Likewise, a lubricant, such as oil, water, or even gold, can optionally be used in a plain bearing or a rolling bearing. Last but not least, a magnetic bearing or, for example, in the case of a very small implementation of the mechanical-electrical generator according to the invention, a ruby ​​bearing, such as those used in watchmaking, can also be used.

[0052] As the list of possible bearing types alone has shown, the details and specifics of the exemplary embodiment described above are not to be understood as limiting. For example, the housing 110 can also be constructed differently from the described three-part structure, which is secured with the aid of screws 120 and nuts 130. For example, the housing 110 can have more or fewer than three parts. With regard to the choice of material, either metal, plastic, or another material can be used. Likewise, individual parts of the housing can be secured using a method other than a screw and a nut. Adhesive bonding represents merely a further exemplary embodiment in this context.

[0053] The electrical connection can also be implemented in a form other than the described contact pins 230. In addition to another plug connection, for example, in the form of a plug or socket, spring-loaded contact pins or other contact surfaces can also be used. In principle, contactless transmission of energy, for example, through magnetic transmission within a transformer, is also conceivable.

[0054] The described embodiment is also not to be understood as limiting with regard to the energy conversion device, in particular the induction coils 220. Rather, the number of induction coils, their spatial arrangement, their specific design, and other features can be varied. It is also not mandatory that the flywheel magnet 180 be able to penetrate the coils 220, even if this brings with it the described advantages. Thus, one or more induction coils can also be connected to the oscillating pendulum 140.

[0055] Furthermore, for example, more than one oscillating magnet 180 can be used on the oscillating pendulum 140. For example, individual or multiple magnets can be attached to the oscillating pendulum 140 on both sides facing the induction coils 220.

[0056] The described design of the field magnets 210 and their attachment to the grub screws 200 should not be understood as limiting. A different geometric arrangement of the field magnets with a larger or smaller number of field magnets can certainly be selected. The design of the adjustment device in the form of the grub screws 200 in conjunction with the corresponding threaded holes in the housing 110 also represents only one possibility and thus an exemplary embodiment of an adjustment device. For example, a different possibility can also be chosen to arrange the field magnets with respect to the vibration level 140 and make them adjustable. One example of this is a lever construction that enables adjustment of the positions of the field magnets 210. Furthermore, it is of course also possible not to implement an adjustment device and thus to make the stop device in the form of the field magnets 210 non-adjustable.

[0057] In principle, it is also possible to base the stop device not on a magnetic interaction, but, for example, on an electrostatic interaction. In this case, for example, the field magnets 210 can be replaced with corresponding electrostatic components, just like the oscillating magnet 180. A possible electrostatic implementation in this case comprises a material that exhibits electrostatic polarization. Examples of this are so-called high-ε materials (e.g., barium titanate or lead titanate) or other electred materials. All of these materials can be manufactured or prepared in such a way that they exhibit permanent electrostatic polarization and thus represent an "electrostatic equivalent" of a permanent magnet. In this case, both the field magnets 210 and the oscillating magnet 180 can be replaced with corresponding electrostatic counterparts.In this case, they must be arranged in such a way that a repulsive, i.e., restoring force is exerted on the components in question when they approach each other spatially.

[0058] Likewise, the energy conversion device can be realized not only on magnetic systems by means of induction coils, but also, for example, by electrostatic converters, as in the following embodiment, which is a micromechanical implementation of a mechanical-electrical generator according to the invention.

[0059] Fig. 3 shows a second embodiment of a mechanical-electrical generator according to the invention in the form of a micromechanically manufactured vibration generator 300. As already mentioned at the beginning of the description of the Fig. 1, in the description of this embodiment, similar reference numerals are used for objects that have functionally identical or functionally similar properties and features, which differ by 200.

[0060] The Fig. The micromechanically manufactured vibration generator 300 shown in Figure 3 thus has a substrate or a stator 310 as its base. The vibration generator 300 also has an oscillating pendulum 340 that is connected to a shaft 360. The stator 310 also has a recess 370, which here is part of the energy conversion device of the vibration generator 300 and has a tooth-shaped structure on its circumference. Arranged inside the recess 370 is a rotor 375 that is connected to the oscillating pendulum 340 and is also part of the energy conversion device. Furthermore, an oscillating magnet 380, which has a north pole and a south pole, is mechanically connected to the oscillating pendulum 340. Two field magnets are mounted on the stator 310, the position of which can be adjusted on the stator 310.The spring magnets 410 are arranged on the stator 310 such that they face the north pole of the oscillating magnet 380 with a north pole and the south pole of the oscillating magnet 380 with a south pole. Because the spring magnets 410 are displaceable in their position relative to the stator 310, the spring characteristic curve resulting from the magnetic interaction of the field magnets 410 and the oscillating magnet 380 can be adjusted, and is therefore also adjustable in this embodiment.

[0061] The functioning of the micromechanically manufactured vibration generator 300, whose basic structure is shown in Fig. 3, which electrostatically converts the kinetic energy of a vibration into an electrical signal, differs from the operation of the Fig. 1. If the vibration generator 300 is excited, for example, by a shock or vibration with a certain vibration frequency, the inertia of the mass of the oscillating pendulum 340 causes it to be deflected from a rest position or equilibrium position. This results in a twisting or deflection of the oscillating pendulum 340, the oscillating magnet 380, and the rotor 375. Due to the orientation of the field magnets 410 relative to the oscillating magnet 380, these in turn exert a restoring force on the oscillating pendulum 340.

[0062] Also in the Fig. In the micromechanically manufactured vibration generator 300 shown in Figure 3, the resulting characteristic curve of the stop device, which is formed by the field magnets 410 and the oscillating magnet 380, can be adjusted using adjustable field magnets 410. This adjustment, which can also be carried out using micromechanical technology, allows the user of the vibration generator 300 to specifically adapt the characteristics of the conversion of mechanical vibrations and stochastic shocks into electrical signals by the vibration generator 300 to the respective application areas. Here, too, the characteristic curve initially runs very flat in the range of small deflection angles around the equilibrium position, so that the vibration generator 300 initially has a low resonant frequency.If the oscillating magnet 380 and the field magnets 410 approach each other further, the force increases disproportionately, so that a certain “de-position damping” can be realized here as well.

[0063] A further reduction in the resonant frequency of the micromechanical vibration generator 300 can be achieved by coupling an oscillating magnet 380, which is comparatively heavy for micromechanical components, to the oscillating pendulum 340. Together with the comparatively "flat" characteristic curve with respect to the stop effect of the stop device provided by the magnetic interaction, the resonant frequency of the micromechanical generator 300 can thus be shifted further to lower frequencies, counteracting a disadvantage that occurs particularly in micromechanical vibration generators. Conventional vibration generators manufactured using micromechanical technology typically have resonant frequencies that are far above technically usable vibration frequencies due to the small, moving masses of the micromechanical components.The micromechanical vibration generator 300 according to the invention thus makes it possible, due to its design with the oscillating magnet 380 attached to the outer end of the oscillating pendulum 340, to shift the resonance frequency of the micromechanical vibration generator 300 into regions of the resonance frequency that are normally only accessible to precision mechanical vibration generators.

[0064] In contrast to the Fig. 1 shown precision mechanical vibration generator 100 is carried out in the Fig. 3, the micromechanical vibration generator 300 converts the kinetic energy in the form of vibrations and shocks into electrical signals via an electrostatic conversion. Fig. In the vibration generator 300 shown in Figure 3, the energy conversion device comprises both the stator 310 and the rotor 375, both of which have a tooth-shaped outer and inner structure, respectively. If a vibration causes the oscillating pendulum 340 to deflect, the tooth-shaped structures of the rotor 375 and the stator 310 are displaced relative to one another due to the mechanical connection of the rotor 375 to the oscillating pendulum 340. This results in a modulation of the distance between the stator 310 and the rotor 375, which can be converted into a voltage change or a current change.

[0065] More precisely, the stator 310 and the rotor 375 form two electrodes of a capacitance or capacitor. Due to the above-described change in the distance of the rotor 375 from the stator 310, a change in the electrical capacitance value occurs, which, depending on the design of the energy conversion device, can be converted into an electrical current or a change in an electrical voltage. If, for example, the stator 310 is connected to a first terminal of an electred component and the rotor 375 is connected to a second terminal of an electred component, a constant electrical voltage is present between the first and second terminals, and thus between the stator 310 and the rotor 375, due to the properties of the electred component, i.e., in particular, due to the "frozen" electrical polarization in the electred material of the component.In this case, a change in the distance between the stator 310 and the rotor 375 causes a change in the capacitance value and thus the charge on the capacitor formed by the stator 310 and the rotor 375, so that in this case an electric current begins to flow between the stator 310 and the rotor 375.

[0066] Another possibility for implementing an electrostatic energy converter is to manufacture the stator 310 and / or the rotor 375 from an electred material or a high-ε material. In this case, it is possible to "freeze" an electrostatic polarization in the various components through suitable pretreatment of the electred material or the high-ε material, so that the capacitor formed by the rotor 375 and the stator 310 has a constant charge. If a deflection of the oscillating pendulum 340 causes the distance between the stator 310 and the rotor 375 to change, this leads to a change in the voltage applied between them.

[0067] As in Fig. As shown in Figure 3 in the form of a micromechanical vibration generator 300, a mechanical-electrical generator according to the invention can be manufactured not only in a mechanical or precision mechanical form, but also offers the possibility of manufacturing such a vibration generator within the scope of micromechanical production. This results in the possibility, for example, of integrating such a micromechanical vibration generator into integrated circuits (IC) or other semiconductor components, so that an external power supply can be dispensed with if necessary.

[0068] Also in the Fig.3, the described features of this specific embodiment are not to be understood as limiting. For example, the stop device, which in the vibration generator 300 comprises the oscillating magnet 380 and the two field magnets 410, can also be implemented electrostatically using electred materials or high-ε materials. Furthermore, in the case of a magnetic stop device, the number of oscillating magnets 380 used can also be adjusted. Adapting the number and arrangement of the oscillating magnets 410 is also conceivable.Furthermore, it may be advisable to operate more than one vibration generator 100, 300 in a serial, parallel or mixed configuration in order to realize, for example, an increase in the voltage of the electrical signal delivered at the electrical output and / or an increase in the current provided at the electrical output.

[0069] Furthermore, depending on the intended application, it may be advisable to supplement each vibration generator or mechanical-electrical generator 100, 300, or a plurality of vibration generators, if such a plurality appears advisable, with one or more processing circuits. Such a processing circuit may, for example, comprise a rectifier circuit that rectifies the AC or AC voltage signals that the vibration generators provide at their outputs. It may also be advisable to implement a processing circuit that changes a voltage value, for example, in the form of a transformer.

[0070] Depending on the circumstances, the inventive method for generating an electrical signal can be implemented in hardware or software. The implementation can take place on a digital storage medium, in particular a floppy disk or CD with electronically readable control signals that can interact with a programmable computer system such that the inventive method for generating an electrical signal can be carried out. In general terms, the invention thus also consists in a computer program product with a program code stored on a machine-readable carrier for carrying out the inventive method when the computer program product runs on a computer. In other words, the invention can thus be realized as a computer program with a program code for carrying out the method when the computer program runs on a computer.

Claims

[1] Mechanical-electrical vibration generator (100; 300) with the following features: a base (110; 310); a swinging pendulum (140; 340) connected to the base (110; 310) in such a way that the swinging pendulum (140; 340) can perform a torsional vibration relative to the base (110; 310) in response to a vibration of the mechanical-electrical vibration generator (100; 300); a stop device (180, 210; 380, 410) which is coupled to the oscillating pendulum (140; 340) in such a way that a complete torsional oscillation is prevented, and the stop device (180, 210; 380, 410) is designed to exert an elastic stop effect on the oscillating pendulum (140; 340) when the oscillating pendulum (140; 340) and the stop device (180, 210; 380, 410) interact; an adjustment device (200) coupled to the stop device (180, 210; 380, 410), wherein the stop device (180, 210; 380, 410) is further configured to make the elastic stop effect adjustable in response to a user's adjustment of the adjustment device (200); an energy converter device (180, 220; 375, 310) configured to convert the rotational oscillation of the oscillating pendulum (140; 340) into an electrical signal; and an electrical output (230) for coupling out the electrical signal to which an electrical load can be coupled, wherein the mechanical-electrical vibration generator (100; 300) is designed as a precision mechanical or micromechanical system. [2] Mechanical-electrical vibration generator (100; 300) according to claim 1, wherein the stop device (180, 210; 380, 410) has a non-linear restoring force related to an equilibrium angle of deflection. [3] Mechanical-electrical vibration generator (100; 300) according to one of the preceding claims, wherein the stop device (180, 210; 380, 410) is designed such that 50% or more of a kinetic energy of the oscillating pendulum (140; 340) is converted into a potential energy by the elastic interaction. [4] Mechanical-electrical vibration generator (100; 300) according to one of the preceding claims, in which the stop device (180, 210; 380, 410) has an oscillating magnet (180; 380) which is coupled to the oscillating pendulum (140; 340) and a spring magnet (210; 410) which is coupled to the base (110; 310), and which are oriented to one another such that when the oscillating magnet (180; 380) approaches the spring magnet (210; 410), the oscillating magnet (180; 380) and the spring magnet (210; 410) exert a repulsive force on one another. [5] Mechanical-electrical vibration generator (100; 300) according to one of claims 1 to 3, wherein the oscillating pendulum (140; 340) has a first electrostatic component and a second electrostatic component of the stop device (180, 210; 380, 410) is coupled to the base (110; 310) such that when the oscillating pendulum (140; 340) approaches the second electrostatic component, the second electrostatic component and the first electrostatic component exert a repulsive force on each other. [6] Mechanical-electrical vibration generator (100; 300) according to one of the preceding claims, further comprising a housing (110) with a recess (190) via which the adjusting device (200) can be operated by the user. [7] Mechanical-electrical vibration generator (100; 300) according to one of the preceding claims, wherein the adjusting device (200) comprises a grub screw (200) which is operable by the user. [8] Mechanical-electrical vibration generator (100; 300) according to one of the preceding claims, wherein the spring magnet (210; 410) is variable in its position relative to the base (110; 310). [9] Mechanical-electrical vibration generator (100) according to one of the preceding claims, wherein the energy conversion device (180; 220) comprises an induction coil (220) and a magnet (180) so that the electrical signal is obtained inductively. [10] Mechanical-electrical vibration generator (100) according to claim 9, wherein the coil (220) is coupled to the base (110) and the magnet (180) is coupled to the oscillating pendulum (140). [11] Mechanical-electrical vibration generator (300) according to one of claims 1 to 8, wherein the energy converter device (310; 375) is designed to obtain the electrical signal electrostatically via a variable capacitance value. [12] Mechanical-electrical vibration generator (100; 300) according to one of the preceding claims, in which the oscillating pendulum (140; 340) and the stop device (180, 210; 380, 410) are designed to cause the oscillating pendulum (140; 340) to undergo the torsional oscillation in response to the vibration at a frequency of less than 125 Hz. [13] Mechanical-electrical vibration generator (100; 300) according to one of the preceding claims, which is designed as the micromechanical system and is integrated in an integrated circuit or a semiconductor component. [14] Method for generating an electrical signal via a mechanical-electrical vibration generator (100; 300) with a base (110; 310), an oscillating pendulum (140; 340) which is connected to the base (110; 310) in such a way that the oscillating pendulum (140; 340) can execute a torsional oscillation relative to the base (110; 310) in response to a vibration of the mechanical-electrical vibration generator (100; 300), a stop device (180, 210; 380, 410) which is coupled to the oscillating pendulum (140; 340) in such a way that a complete torsional oscillation is prevented, and the stop device (180, 210; 380, 410) is designed to exert an elastic stop effect on the oscillating pendulum (140; 340) when the oscillating pendulum (140; 340) and the stop device (180, 210; 380, 410) interact, an adjustment device (200) which is coupled to the stop device (180, 210; 380, 410), wherein the stop device (180, 210;380, 410) is further designed to make the elastic stop effect adjustable in response to a user setting on the adjustment device (200), an energy converter device (180, 220; 375, 310) which is designed to convert the torsional oscillation of the oscillating pendulum (140; 340) into an electrical signal, and an electrical output (230) to couple out the electrical signal to which an electrical load can be coupled, with the following steps:; Performing a torsional oscillation using the oscillating pendulum (140; 340) in response to a vibration; Exerting an elastic stop effect on the oscillating pendulum (140; 340) using the stop device (180, 210; 380, 410) so that a complete torsional oscillation is prevented; Converting the torsional vibration into an electrical signal using the energy conversion device (180, 220,; 375,310); and decoupling the electrical signal using the electrical output (230), wherein the mechanical-electrical vibration generator (100; 300) is designed as a precision mechanical or micromechanical system. [15] The method of claim 14, further comprising a step of adjusting the stop means (180, 210; 380, 410) using the adjusting means (200) to make the elastic stop action tunable.

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