Actuator for converting an electrical signal into a positioning of an actuator corresponding to the signal

Abstract

An actuator (100, 200, 300, 400, 500) is described with a composite (10, 20, 30, 40), a controller (7) to which a signal (S) can be applied on the input side, a temperature control device (9, 9') connected to the controller (7), and a mechanical converter (11, 19, 37). The composite (10, 20, 30, 40) comprises a rod-shaped first component (1) and a rod-shaped second component (3) connected to the first component (1), the thermal expansion coefficients of which are identical. The temperature control device (9, 9') is designed to bring about a temperature difference (ΔT) between a temperature (T1) of the first component (1) and a temperature (T2) of the second component (3), which temperature difference can be predetermined by means of the controller (7) in accordance with the input signal (S).The mechanical converter (11, 19, 37) converts a property of a deformation state of the composite (10, 20, 30, 40) that depends on the size of the temperature difference (ΔT) into a corresponding positioning of an actuator (13) of the actuator (100, 200, 300, 400, 500).

Description

The invention relates to an actuator which is designed to convert an electrical signal into a positioning of an actuator corresponding to the signal.Actuators are used in a large number of different applications for effecting electrically controllable mechanical displacements of components. In this case, the respective component is moved by means of the actuator by positioning an actuator of the actuator that can be predefined on the basis of an electrical signal.Correspondingly designed actuators are used, for example, for opening and / or closing valves, for actuating switches, and also for opening and / or closing flaps.From the prior art, different types of actuators are known, with which controlled displacements of different size can be effected depending on the type.To achieve greater displacements, such as displacements on the order of one or more millimeters, actuators comprising a stepper motor and a mechanical converter may be used, for example. Converters comprising e.g. spindles, toothed racks or friction wheels are used as converters in these actuators, which converters convert a rotational movement which can be generated by means of the stepper motor into a linear movement of an actuator.To achieve small displacements, such as displacements on the order of greater than or equal to several hundred micrometers, it is possible to use, for example, thermal actuators, such as bimetallic actuators, in which the positioning of the actuator is effected by a deflection of a bimetallic element which can be generated by means of a heating device.Bimetallic elements have the advantage that they are cost-effective. However, it is disadvantageous that the deformation state of bimetallic elements depends on their absolute temperature. Accordingly, with bimetallic actuators it must be ensured that the deflection to be brought about by a corresponding actuation of the heating device cannot already occur as a result of changes in the ambient temperature. As a result, the ambient temperature range in which bimetallic actuators can be used must be correspondingly greatly restricted, and / or the correspondingly designed bimetallic element must be heated to temperatures lying significantly above the maximum ambient temperature to be expected in order to effect a controllable deformation. Both limitations of the ambient temperature range and heating the bimetal to correspondingly high temperatures limit the applications in which bimetallic actuators may be used.Comparable problems also occur in connection with thermal actuators which comprise a working volume of a medium, which can be heated by means of a heating device and through whose thermal volume expansion a piston is moved. In these actuators, the thermal expansion of the working volume depends on the absolute temperature of the medium, which also changes as a function of the ambient temperature.It is an object of the invention to specify a thermal actuator for positioning an actuator, with which the positioning of the actuator in a relatively wide ambient temperature range can be carried out as precisely as possible and / or substantially independently of the ambient temperature.For this purpose, the invention comprises an actuator witha composite comprising a rod-shaped first component and a rod-shaped second component connected to the first component at least at one end, wherein the first component and the second component have identical thermal expansion coefficients,a controller to which a signal can be applied on the input side,a temperature control device connected to the controller and configured to cause a temperature difference, which can be specified by means of the controller in accordance with the input signal, between a temperature of the first component and a temperature of the second component, anda mechanical converter which converts a property of a deformation state of the composite depending on the magnitude of the temperature difference into a positioning corresponding thereto of an actuator of the actuator which is formed as a component of the converter or is connected to the converter.The identical coefficients of thermal expansion of the first component and of the second component and the implementation of the property of the composite which is dependent on the magnitude of the temperature difference set by means of the controller offer the advantage that a precise positioning of the actuator can be effected with the actuator in a very large ambient temperature range, which positioning is substantially independent of the ambient temperature.A first variant consists in thatthe first component and the second component are arranged in a plane parallel offset from one another,an end of the first component is connected to an end of the second component via a rigid base; andthe converter converts a length difference, dependent on the temperature difference, between a length of the first component and a length of the second component into a positioning of the actuator corresponding to the length difference.One embodiment of the first variant provides that the converter is designed as a first lever or comprises a first lever, wherein the first lever:an end forming or comprising the actuator on which the actuator is arranged or which is mechanically connected to the actuator, andan end region opposite the end, which is connected via a first connection to a free end of the first component facing away from the base and via a second connection spaced apart from the first connection along a longitudinal axis of the first lever to a free end of the second component facing away from the base.A development of this embodiment provides thatthe end of the first lever is connected to a first end region of a second lever via a deflection device,the first end region of the second lever is additionally connected to the base via a further connection spaced apart from the deflecting device in a direction running parallel to the longitudinal axis of the second lever, andthe actuator is formed by a region of a second end region of the second lever facing away from the deflection device, projecting perpendicularly to the longitudinal axis of the second lever in the direction facing away from the first lever, is arranged on a region of the second lever facing away from the deflection device, is formed by a region of the second lever facing away from the deflection device, or is mechanically connected to a region of the second lever facing away from the deflection device.Embodiments of this refinement consist in the fact thatthe second lever runs parallel to the first lever at the same temperature of the first component and the second component, and / orthe deflecting device and the further connection are elastic and / or are designed as connecting webs.Developments of the first variant provide thatthe first component, the second component, the base, the first connection, the second connection, the further connection and / or the converter or at least partial regions of the converter are formed as regions of a one-piece component or of a one-piece, single- or multi-layer printed circuit board, and / orthe first connection and the second connection are each designed as an elastic connection and / or as a connecting web, the width of which is virtually smaller than a width of the first component and of the second component.A further development of the first variant consists in thata first strain gauge connected to the controller for measuring a linear expansion of the first component is arranged on the first component,a second strain gauge connected to the controller for measuring a linear expansion of the second component is arranged on the second component, andthe controller is configured to control the positioning of the actuator controlled by the controller via a control of the temperature control device corresponding to the signal based on a difference of the linear expansion of the first component measured with the first strain gauge and the linear expansion of the second component measured with the second strain gauge.A second variant consists in the fact that the first component and the second component are arranged one above the other in the assembly and are thermally insulated from one another, and the converter converts a deflection of the assembly, which deflection is dependent on the temperature difference, into the positioning of the actuator corresponding thereto.A first development of the second variant provides that the composite is freely movable apart from an end of the composite fixed in its position, clamped in a clamping device or mounted on a carrier, and the converter is designed to convert a deflection, corresponding to the deflection dependent on the temperature difference, of a freely movable end of the composite connected to the converter and opposite the fixed end into the positioning of the actuator corresponding thereto.A second development of the second variant consists in the fact that the mutually opposite outer ends of the composite are each arranged in or on a bearing, in a bearing designed as a surround or on a bearing surface serving as a bearing in such a way that a central region of the composite situated therebetween is freely movable, and the converter is designed to convert a deflection of the central region of the composite connected to the converter (37), which deflection corresponds to the deflection dependent on the temperature difference, into the positioning of the actuator corresponding thereto.Developments of actuators according to the second variant consist in thatthe first component is thermally insulated from the second component by each of the two outer ends of the first component being connected to one of the two outer ends of the second component via a spacer or a spacer made of a thermal insulator, made of glass, plastic or ceramic, or by the first component being connected to the second component over its entire surface by an insulation layer arranged between the first component and the second component or an insulation layer made of plastic,the composite is constructed from individual parts, is formed as a component produced by a 3-D printing method, is formed as a multi-ply printed circuit board, or comprises two identically constructed printed circuit boards, one of which forms the first component and the other of which forms the second component, and / orthe temperature control device comprises at least one element, each arranged between the first component and the second component and each configured as a heating and cooling element or as a Peltier element, wherein the or each element is each arranged and configured such that it heats one of the two components adjoining it simultaneously and cools the respective other component in order to generate a temperature difference corresponding to the signal when the temperature control device or each element is controlled accordingly by the controller.According to a further development, the actuator according to the second variant comprises at least one strain gauge, which is respectively arranged on the first component or on the second component and is connected to the controller, for the measurement-technology detection of a variable dependent on the deflection of the composite, and the controller is designed to regulate the positioning of the actuator, which is controlled by the controller via an actuation of the temperature control device corresponding to the signal, on the basis of the deflection detected with the strain gauge or gauges.A further refinement of the actuators described here provides thata first temperature sensor connected to the controller for measuring the temperature of the first component is arranged on the first component,a second temperature sensor connected to the controller for measuring the temperature of the second component is arranged on the second component, andthe controller is configured to control the temperature difference to be effected by means of the temperature control device according to the signal based on a difference between the temperature of the first component measured with the first temperature sensor and the temperature of the second component measured with the second temperature sensor.According to a further development, the actuator comprises a measuring device connected to the controller for measuring at least one variable dependent on the deformation state of the composite and / or at least one variable dependent on the position of the control element, wherein the controller is designed to regulate the positioning of the control element controlled by the controller via an actuation of the temperature control device corresponding to the signal on the basis of the or each variable measured by the measuring device.Further developments of the latter development consist in that the measuring device:a distance sensor, a capacitive distance sensor, a magnetic distance sensor or an optical distance sensor for detecting a distance of the actuator from a predetermined reference point, which distance is dependent on the positioning of the actuator, by measurement, and / orat least one distance sensor, a capacitive distance sensor, a magnetic distance sensor or an optical distance sensor for metrological detection of a variable of the composite dependent on the deformation state of the composite.A further development provides that the temperature control device comprises at least one element arranged on the first component, comprises at least one element arranged on the second component or comprises at least two elements, of which at least one is arranged on the first component (1) and at least one is arranged on the second component, and the or each element of the temperature control device is in each case designed as an element which can be controlled by means of the controller and can be operated as a heating element and / or as a cooling element.Further developments consist in the fact that the first component and the second component are of the same length at a predetermined reference temperature, and / or in each case:a base surface having a length of 10 mm to 100 mm and a width of 1 mm to 10 mm, and / or having a thickness of 0.5 mm to 3 mm running perpendicular to the base surface,as a single-layer or multi-layer printed circuit board or as a printed circuit board region of a single-layer or multi-layer printed circuit board, and / oras a multi-layer component, which comprises at least one printed circuit board layer made of a non-metallic printed circuit board material and at least one metallic layer made of a metal or of copper.The invention and its advantages will now be explained in more detail with reference to the figures of the drawing, in which a plurality of exemplary embodiments are shown. Identical elements are provided with the same reference numerals in the figures. FIG. 1 shows: an actuator having two components arranged offset parallel to one another in a plane at the same temperature of the components; FIG. 2 shows the actuator shown in FIG. 1 with an unequal temperature of the components; FIG. 3 shows a modification of the actuator shown in FIG. 1 at the same temperature of the components; FIG. 4 shows the actuator shown in FIG. 3 with an unequal temperature of the components; FIG. 5 shows: an actuator with two components arranged one above the other in a composite fixed on the end side; FIG. 6 shows: an actuator having two components arranged one above the other in a composite mounted on both ends; FIG. 7 shows: a multilayer component; and FIG. 8 shows: an actuator with a temperature control device comprising Peltier elements.The invention relates to a thermal actuator. A first exemplary embodiment of this is shown in FIG. 1. The actuator 100 comprises a composite 10, which comprises a rod-shaped first component 1 and a rod-shaped second component 3 connected to the first component 1 at least at one end.The first component 1 has a predefined first length at a predefined reference temperature. The second component 3 has a predefined second length at the predefined reference temperature. A presently preferred embodiment shown in FIG. 1 consists in that the first component 1 and the second component 3 are of equal length at the reference temperature. Alternatively, depending on the configuration of the actuator 100, however, they can also be of different lengths at the same reference temperature.The dimensions of the first and second components 1, 3 can be freely predefined within wide limits. At the reference temperature, such as a room temperature of 21° C., they each have, for example, a base surface with a length of 10 mm to 100 mm and a width of 1 mm to 10 mm, and / or a thickness of 0.5 mm to 3 mm running perpendicular to the base surface.The first component 1 and the second component 3 have identical coefficients of thermal expansion. This can be achieved, for example, by the fact that the first component 1 and the second component 3 are of identical construction, consist of the same material, or consist of the same composite material, wherein the composite material comprises at least two layers arranged one on top of the other and connected to one another. One configuration provides that the first component 1 and the second component 3 are each designed as a printed circuit board or as a printed circuit board region of a single- or multilayer printed circuit board.The composite 10 comprising the first component 1 and the second component 3 can be formed in different ways depending on the arrangement of the first component 1 and the second component 3.FIG. 1 shows an exemplary embodiment in which the first component 1 and the second component 3 are arranged in a plane in a manner offset parallel to one another, and one end of the first component 1 is connected to one end of the second component 3 running parallel thereto via a rigid base 5.Furthermore, the actuator 100 comprises a controller 7 to which an electrical signal S can be applied on the input side, a temperature control device 9 connected to the controller 7, and a mechanical converter 11.The temperature control device 9 is designed to bring about a temperature difference ΔT, which can be predefined by means of the controller 7 in accordance with the input signal S, between a temperature T 1 of the first component 1 and a temperature T 2 of the second component 3.A suitable temperature control device 9 is, for example, a device which comprises at least one element E 1 arranged on the first component 1 and each operable as a heating element and / or as a cooling element and controllable by means of the controller 7 and / or at least one element E 2 arranged on the second component 3 and each operable as a heating element and / or as a cooling element and controllable by means of the controller 7. Suitable elements E 1, E 2 that can be operated exclusively as heating elements are, for example, resistance elements. Suitable elements E 1, E 2 operable both as a heating element and as a cooling element are, for example, Peltier elements.FIG. 1 shows an exemplary embodiment in which the temperature control device 9 comprises a plurality of elements E 1 arranged on the first component 1 and controllable by means of the controller 7 and a plurality of elements E 2 arranged on the second component 3 and controllable by means of the controller 7. Temperature control devices 9 having at least one element E 1, E 2 arranged on the first component 1 and at least one element E 1, E 2 arranged on the second component 3 offer the advantage that the temperature difference ΔT can be changed significantly more quickly by a corresponding control of the elements E 1, E 2 by the controller 7 as a function of the signal S than in the case of alternatively usable temperature control devices 9 in which at least one element E 1 or E 2 is arranged only on one of the two components 1, 3.In actuators 100 in which the first component 1 and the second component 3 are each designed as a printed circuit board or as a printed circuit board region of a printed circuit board, the connection lines of the elements E 1, E 2 of the temperature control device 9 are each designed, for example, as lines running at least partially on and / or within the printed circuit board. This offers the advantage of low production costs.The mechanical converter 11 is designed to convert a property of a deformation state of the composite 10 comprising the first component 1 and the second component 3 which is dependent on the magnitude of the temperature difference ΔT into a positioning, corresponding thereto, of an actuator 13 of the actuator 100 which is designed as a component of the converter 11 or is connected to the converter 11.The identical coefficients of thermal expansion of the first component 1 and of the second component 3 offer the advantage that a property of the composite 10 which is dependent on the magnitude of the temperature difference ΔT can be or is converted by the converter 11 and is substantially independent of the ambient temperature. For this purpose, depending on the configuration of the composite 10 and / or the property of the composite 10 used for positioning the actuator 13, different types of mechanical converters 11 can be used.In the exemplary embodiment illustrated in FIG. 1, a length difference ΔL, which is dependent on the temperature difference ΔT, between the length L 1 of the first component 1 which is dependent on the temperature T 1 of the first component 1 and the length L 2 of the second component 3 which is dependent on the temperature T 2 of the second component 3 is used as a property of the deformation state of the composite 10. This difference in length ΔL is converted by the converter 11 into the positioning of the actuator 13 corresponding thereto.FIG. 1 shows the composite 10 in a deformation state which it assumes at the same temperature T 1, T 2 of the first component 1 and of the second component 3. In the example shown in FIG. 1, the first component 1 and the second component 3 have the same length at the predetermined reference temperature. Due to the identical coefficients of thermal expansion, they accordingly always have the same length irrespective of their absolute temperature T1, T2which may also be dependent on the ambient temperature, given a temperature difference ΔT of 0° C.FIG. 2 shows the actuator 100 shown in FIG. 1, wherein the composite 10 in FIG. 2 is shown in a deformation state which it assumes when the temperature T 1 of the first component 1 is truly greater than the temperature T 2 of the second component 3. In the case of such a temperature difference ΔT, referred to below as a positive temperature difference ΔT(T 1>T 2), where ΔT: =T 1- T 2>0° C., the length L 1 of the first component 1 is truly greater than the length L 2 of the second component 3.Similarly, for a temperature difference ΔT, referred to as negative temperature difference ΔT(T 1<T 2) below, where ΔT: =T1-T2<0° C., in which the temperature T 1 of the first component 1 is truly less than the temperature T 2 of the second component 3, a deformation state is established in which the length L 1 of the first component 1 is truly less than the length L 2 of the second component 3.In the case of an increase in the temperature difference ΔT to a positive temperature difference ΔT(T1>T2) proceeding from a temperature difference ΔT of 0° C. and effected by means of the controller 7, and also in the case of a drop in the temperature difference ΔT to a negative temperature difference ΔT(T1<T2) effected by means of the controller 7, the change in the length difference ΔL of the length L1of the first component 1 and of the length L2of the second component 3 which is associated therewith is converted by means of the converter 11 into a displacement Δx of the actuator 13 which corresponds to the change in the length difference ΔL.Here, the equality of the lengths of the components 1, 3 at the same temperature T 1, T 2 of the components 1, 3 in combination with their identical thermal expansion coefficients offers the advantage that the difference in length ΔL is not only proportional to the difference in temperature ΔT, but at the same time is also substantially independent of the absolute values of the temperature T 1 of the first component 1 and of the temperature T 2 of the second component 3, which absolute values are possibly also dependent on the ambient temperature.With regard to the implementation of the length difference ΔL, FIGS. 1 and 2 show an exemplary embodiment in which the converter 11 is designed as a simple first lever for illustrating the principle. The first lever includes an end forming the actuator 13 at which the actuator 13 is disposed or which is mechanically connected to the actuator 13. In addition, an end region of the first lever opposite this end is connected via a first connection 15 to a free end of the first component 1 remote from the base 5 and via a second connection 17 spaced apart from the first connection 15 along the longitudinal axis of the first lever to a free end of the second component 3 remote from the base 5. Accordingly, the converter 11 designed here as a first lever converts the relative position of the two connections 15, 17 connected to the end region of the first lever, which relative position corresponds to the difference in length ΔL of the two components 1, 3, into the positioning of the actuator 13 corresponding to the difference in temperature ΔT. In this case, the magnitude of the displacements Δx of the actuator 13 which can be effected by means of the controller 7 in accordance with the signal S can be predetermined over the length of the first lever.An optional embodiment shown in FIGS. 1 and 2 consists in that the first component 1, the second component 5, the base 5, the connections 15, 17 and / or the converter 11 or at least partial regions of the converter 11, and optionally also the actuator 13, are each formed as regions of a one-piece component, such as a single-layer or multi-layer printed circuit board, with a correspondingly formed base surface.Alternatively or additionally, the connections 15, 17 are designed, for example, as elastic connections to a certain extent. As shown in FIGS. 1 and 2, this can be effected, for example, by the connections 15, 17 being designed as connecting webs whose width is virtually smaller than the width of the first component 1 and of the second component 3.Instead of the converter 11 shown in FIGS. 1 and 2, a converter formed in another manner and comprising one or more conversion stages can of course also be used for converting the length difference ΔL into the corresponding positioning of the actuator 13.An embodiment of an actuator 200 with a converter 19 comprising a plurality of conversion stages is illustrated in FIGS. 3 and 4. Just like the actuator 100 shown in FIGS. 1 and 2, this actuator 200 also has the first component 1, the second component 3 connected to the first component 1 via the base 5, the controller 7 and the temperature control device 9, which are each designed in the manner described above. Here, too, the composite 20 comprising the first component 1 and the second component 3 arranged in parallel offset thereto in the same plane is shown in FIG. 3 in a deformation state which is established at the same temperature T 1, T 2 of the first and second components 1, 3 and in FIG. 4 in a deformation state which is established at a negative temperature difference ΔT (T 1<T 2) at which the temperature T 1 of the first component 1 is truly lower than the temperature T 2 of the second component 3.Just like the translator 11 shown in FIGS. 1 and 2, the translator 19 shown in FIGS. 3 and 4 also comprises a first lever 21, the end region of which is connected to the first component 1 via the first connection 15 and to the second component 3 via the second connection 17 spaced apart from the first connection 15 in a direction running parallel to the longitudinal axis of the first lever 21.In FIGS. 3 and 4, the end of the first lever 21 opposite the end region is connected at the end side via a deflection device 23 to a first end region of a second lever 25. The first end region of the second lever 25 is additionally connected to the base 5 of the actuator 200 via a further connection 27 and a connecting piece 29 which are spaced apart from the deflection device 23 in a direction running parallel to the longitudinal axis of the second lever 25. The connecting piece 29 is optionally formed, for example, as an integral component of the base 5 or as a component connected to the base 5.FIGS. 3 and 4 show an exemplary embodiment in which the actuator 13 is formed by a region of the second end region of the second lever 25 facing away from the deflecting device 23, which region protrudes perpendicularly to the longitudinal axis of the second lever 25 in the direction facing away from the first lever 21. Alternatively, in the actuator 200 shown in FIGS. 3 and 4, however, the actuator 13 can also be formed, for example, by another region of the second lever 25 facing away from the deflecting device 23, be arranged on a region of the second lever 25 facing away from the deflecting device 23, or be mechanically connected to a region of the second lever 25 facing away from the deflecting device 23.An optional embodiment shown in FIGS. 3 and 4 consists in that the second lever 25 runs parallel to the first lever 21 at the same temperature T 1, T 2 of the first component 1 and of the second component 3. However, this is not absolutely necessary. Alternatively, the second lever can also be inclined with respect to the first lever at the same temperature T 1, T 2 of the first component 1 and of the second component 3.If the second component 3 is arranged on the side of the composite 20 facing the deflecting device 23, as shown in FIGS. 3 and 4, a negative temperature difference ΔT(T 1<T 2), at which the linear extent of the second component 3 is accordingly greater than that of the first component 1, leads to a deflection, corresponding to the linear difference ΔL, of the end of the first lever 21 connected to the deflecting device 23 in a first direction R 1 facing away from the base 5 and indicated by an arrow in FIG. 4. This deflection is transmitted via the deflection device 23 to the first end region of the second lever 25 remote from the actuator 13 and connected to the base 5 via the further connection 27. This transmission in turn causes a deflection of the second end region of the second lever 25 facing away from the deflection device 23 in a second direction R 2 facing the base 5, which is likewise indicated by an arrow in FIG. 4.Similarly, a positive temperature difference ΔT(T1>T2), in which the longitudinal extension of the first component 1 is greater than that of the second component 3, leads to a deflection, corresponding to the longitudinal difference ΔL, of the end of the first lever 21 connected to the deflection device 23 in a direction facing the base 5. This deflection is also transmitted via the deflection device 23 to the first end region of the second lever 29 remote from the actuator 13 and connected to the base 5 via the further connection 27. This transmission causes a deflection of the second end region of the second lever 25 facing away from the deflection device 23 in a direction facing away from the base 5.An optional embodiment of the exemplary embodiment shown in FIGS. 3 and 4 consists in the fact that the first component 1, the second component 3, the base 5 including the connecting piece 29, the connections 15, 17, the further connection 27, and / or the converter 19 or at least partial regions of the converter 19, and optionally also the actuator 13, are each formed as regions of a one-part component, such as a single-layered or multi-layered printed circuit board, having a correspondingly formed base surface. Here, too, the first and the second connection 15, 17, the deflection device 23 and the further connection 27 are designed, for example, to a certain extent elastically and / or as connecting webs, wherein the elasticity of the connecting webs can be effected or is effected here, for example, by their correspondingly small width.FIGS. 5 and 6 each show a further exemplary embodiment of an actuator 300, 400. These actuators 300, 400 also each comprise the first component 1, the second component 3, the controller 7 and the temperature control device 9, which are each configured in the manner described above. In contrast to the exemplary embodiments shown in FIGS. 1 to 4, the first component 1 and the second component 3 in the exemplary embodiments shown in FIGS. 5 and 6 are each arranged one above the other in a composite 30, 40 and are thermally insulated from one another.In the exemplary embodiment illustrated in FIG. 5, each of the two outer ends of the first component 1 is connected to one of the two outer ends of the second component 3 for this purpose in each case via a spacer 31, such as a spacer 31 made of a thermal insulator, such as glass, plastic or ceramic. In this embodiment, a cavity 32 that contributes to the thermal insulation is enclosed between the two components 1, 3, one of the two spacers 31 being adjacent to each of its opposite ends.FIG. 6 shows an alternative embodiment in which the first component 1 is connected over its entire surface to the second component 3 by an insulation layer 33, such as a plastic layer, arranged between the two components 1, 3.Regardless of the configuration in this regard, the composite 30, 40 of the actuators 300, 400 illustrated in FIGS. 5 and 6 is constructed, for example, from individual parts. In this case, the composite 30, 40 comprises, for example, a printed circuit board which forms the first component 1 and is connected via the spacers 31 or the insulation layer 33 to a printed circuit board which is structurally identical thereto and forms the second component 3. Alternatively, the respective composite 30, 40 is formed, for example, as a single, correspondingly constructed, multilayer printed circuit board or as a component produced by a 3-D printing method.When the first and second components 1, 3 are arranged one above the other in the composite 30, 40, a deformation state illustrated in FIGS. 5 and 6 results at the same temperature T 1, T 2 of the first and second components 1, 3, in which the first component 1 and the second component 3 run plane-parallel to one another. In contrast, positive temperature differences ΔT(T1>T2) and negative temperature differences ΔT(T1<T2) each lead to a bending of the composite 30, 40 in a direction corresponding to the sign of the temperature difference ΔT. These deformation states occurring as a function of the temperature difference ΔT can be used in different ways for positioning the actuator 13.FIG. 5 shows an embodiment in which the composite 30 is freely movable apart from an end of the composite 30 fixed in its position. As shown in FIG. 5, the end of the composite 30 to be fixed is clamped for this purpose, for example, in a clamping device 35. Alternatively, the end to be fixed can, however, also be mounted on a carrier or held in its position in another manner.Regardless of the type of fixing, a positive temperature difference ΔT(T1>T2) leads to a deformation state V30(T1>T2) schematically represented under the composite 30 in FIG. 5, in which the free end of the composite 30 opposite the fixed end is deflected in a first direction running perpendicular to the longitudinal axis L of the composite 30 at the same temperature T1, T2 of the components 1, 3 by a distance Δx1corresponding to the temperature difference ΔT relative to the longitudinal axis L. Analogously, a negative temperature difference ΔT(T1<T2) leads to a deformation state V30(T1<T2) schematically represented in FIG. 5 above the composite 30, in which the free end of the composite 30 is deflected with respect to the longitudinal axis L by a distance Δx2corresponding to the temperature difference ΔT in a second direction running perpendicular to the longitudinal axis L of the composite 30 at the same temperature T1, T2of the components 1, 3 and opposite to the first direction.Accordingly, in the exemplary embodiment shown in FIG. 5, the deflection of the free end of the composite 30 corresponding to the deflection dependent on the temperature difference ΔT is used as a property of the deformation state of the composite 30. This deflection is converted by the converter 37 connected here to the free end of the composite 30 into the positioning of the actuator 13 corresponding thereto. The converter 37 shown in FIG. 5 merely as a possible embodiment comprises, for example, a transmission rod, one end of which is connected to the free end of the composite 30 and the other end of which comprises the actuator 13 or is connected to the actuator 13.In the exemplary embodiment illustrated in FIG. 6, the mutually opposite outer ends of the composite 40 are each arranged in or on a bearing 39, 41 in such a way that the central region of the composite 40 located therebetween is freely movable. Suitable bearings are, for example, bearing surfaces, such as, for example, the bearing surface shown as an example in the right-hand half of FIG. 6 and serving as bearing 39, on each of which one of the two outer ends of the composite 40 rests. Alternatively, suitable bearings are enclosures, such as the enclosure shown as an example in the left-hand half of FIG. 6, serving as a bearing 41, into each of which one of the two outer ends of the composite 40 projects and the interiors of which are truly larger than the outer dimensions of the end of the composite 40 inserted therein.Regardless of the type of bearing, the composite 40 assumes, in the case of a positive temperature difference ΔT(T1>T2), a deformation state V40(T1>T2), which is schematically illustrated above the composite 40 in FIG. 6, in which deformation state the central region of the composite 40 is deflected by a distance Δy1corresponding to the magnitude of the temperature difference ΔT, on account of the greater linear extent of the first component 1 in a first direction running perpendicular to the longitudinal axis L of the composite 40 at the same temperature of the components 1, 3. Analogously, in the case of a negative temperature difference ΔT(T1<T2), the composite 40 assumes a deformation state V40(T1<T2), which is schematically illustrated under the composite 40 in FIG. 6, in which the central region of the composite 40 is deflected by a distance Δy2corresponding to the magnitude of the temperature difference ΔT, on account of the greater linear extent of the second component 3 in a second direction running perpendicular to the longitudinal axis L of the composite 40 at the same temperature of the components 1, 3 and opposite the first direction.Accordingly, in the exemplary embodiment illustrated in FIG. 6, the deflection of the central region of the composite 40 corresponding to the deflection dependent on the temperature difference ΔT is used as a property of the deformation state of the composite 40, which deflection is converted by the converter 37 connected here to the central region of the composite 40 into the positioning of the actuator 13 corresponding thereto. Similarly to the embodiment shown in FIG. 5, the converter 37 shown in FIG. 6 also comprises, for example, a transmission rod, one end of which is connected to the middle end of the linkage 40 and the other end of which comprises the actuator 13 or is connected to the actuator 13.The actuators according to the invention have the aforementioned advantages. Individual components of the actuators can have optional configurations that can be used individually and / or in combination with one another.An optional configuration consists in the fact that the first component 1 and the second component 3 are designed as multilayer components which each comprise at least one printed circuit board layer 43 made of a non-metallic printed circuit board material and at least one metallic layer 45 made of a metal, such as copper. An exemplary embodiment of this is shown in FIG. 7. In this case, each component 1, 3 comprises, for example, in each case a metallic layer 45 arranged on a first outer side of the printed circuit board layer 43 and / or a metallic layer 45 arranged on a second outer side of the printed circuit board layer 43 opposite the first outer side. An optional embodiment provides that both components 1, 3 in each case comprise a second printed circuit board layer 43 shown as an option in dashed lines in FIG. 7 and a metallic layer 45 is arranged between the two printed circuit board layers 43.Regardless of the number of circuit board layers 43 and of the metallic layers 45, each metallic layer 45 has the advantage that a more uniform temperature distribution over the entire length L 1, L 2 of the first and second components 1, 3 is achieved across it.A further optional configuration illustrated in FIGS. 1, 2 and 5 and analogously also usable in the other exemplary embodiments consists in a first temperature sensor 47 connected to the controller 7 for measuring the temperature T 1 of the first component 1 being arranged on the first component 1, and a second temperature sensor 48 connected to the controller 7 for measuring the temperature T 2 of the second component 3 being arranged on the second component 3. In this embodiment, the controller 7 is configured to regulate the temperature difference ΔT to be effected by means of the temperature control device 9 in accordance with the signal S on the basis of a difference between the temperature T 1 of the first component 1 measured by the first temperature sensor 47 and the temperature T 2 of the second component 3 measured by the second temperature sensor 48. This form of feedback-based control of the temperature difference ΔT offers the advantage that an even more precise positioning of the actuator 13 can be effected by this means.A further configuration which can be used in conjunction with actuators, such as the actuators 300 illustrated in FIG. 5, in which the first component 1 and the second component 3 are arranged one above the other in the composite 30, consists in using, instead of the temperature control device 9 illustrated in FIG. 5, a temperature control device 9' which comprises at least one element E arranged in each case between the first component 1 and the second component 3. FIG. 8 shows, as an exemplary embodiment, an actuator 500 which, apart from the temperature control device 9', is of identical construction to the actuator 300 illustrated in FIG. 5. In the temperature control device 9' shown in FIG. 8, each element E is designed as a heating and cooling element, for example as a Peltier element. The or each element E is respectively arranged and configured such that, in order to generate a temperature difference ΔT corresponding to the signal S, it heats one of the two components 1, 3 adjoining it simultaneously and cools the respective other component 3, 1 when the temperature control device 9' or each element E is controlled accordingly by the controller 7.The temperature control device 9' shown in FIG. 8 offers the advantage of a simpler construction comprising fewer individual parts and a correspondingly simplified, synchronous actuation of each element E. A further advantage consists in the fact that the selection of the heated and the cooled components 1, 3 can be predefined by the controller 7 and can be changed by the controller 7 as a function of the signal S. This offers the advantage of a correspondingly low latency time between changes in the signal S and the associated changes in the positioning of the actuator 13.A further optional embodiment consists in that the actuator 100, 200, 300, 400, 500 comprises a measuring device connected to the controller 7 for measuring at least one variable dependent on the deformation state of the composite 10, 20, 30, 40 and / or at least one variable dependent on the position of the actuator 13. In this case, the controller 7 is designed to control the positioning of the actuator 13 controlled by the controller 7 via an actuation of the temperature control device 9, 9' corresponding to the signal S on the basis of the or each variable measured by the measuring device. This feedback-based control, which can also be used alternatively or in addition to the control carried out by means of the temperature sensors 47, 48, also offers the advantage that an even more precise positioning of the actuator 13 can be effected by this means.In this case, the measuring device can comprise different types of sensors depending on the configuration of the actuator 100, 200, 300, 400, 500 and / or the variable(s) to be measured.As shown by way of example in FIGS. 1 and 2, the measuring device comprises, for example, a distance sensor 49 which can also be used analogously in the other actuators 200, 300, 400, 500 described here for the measurement of a distance of the actuator 13 from a predetermined reference point P 1 which is dependent on the positioning of the actuator 13. In this case, the distance sensor 49 is designed, for example, as a capacitive distance sensor which comprises a capacitor having a capacitance which is dependent on the distance. FIGS. 1 and 2 show, as an example, a capacitor including an electrode 51 attached to the actuator 13 and an electrode 53 attached to the reference point P 1. Alternatively, however, a distance sensor operating according to another measuring principle, such as a magnetic distance sensor or an optical distance sensor, can also be used.In conjunction with the distance sensor 49, the controller 7 is designed, for example, to regulate the positioning of the actuator 13, which is controlled by the controller 7 via the control of the temperature control device 9 corresponding to the signal S, on the basis of the distance measured by means of the distance sensor 49.FIGS. 3 and 4 show an exemplary embodiment which can be used in conjunction with actuators, such as the actuators 100, 200 shown in FIGS. 1 to 4, for example, in which the first component 1 and the second component 3 are arranged offset parallel to one another in a plane, in which the measuring device comprises a first strain gauge 55, arranged on the first component 1 and connected to the controller 7, for the measurement-wise detection of the linear extent of the first component 1 and a second strain gauge 57, arranged on the second component 3, connected to the controller 7, for the measurement-wise detection of the linear extent of the second component 3. In this embodiment, the controller 7 is designed to regulate the positioning of the actuator 13, which is controlled by the controller 7 via the control of the temperature control device 9 corresponding to the signal S, on the basis of a difference between the longitudinal expansions of the first component 1 and the second component 3 measured with the two strain gauges 55, 57.Analogously, the measuring device in conjunction with actuators, such as the actuators 300, 400, 500 illustrated in FIGS. 5, 6 and 8, in which the first component 1 and the second component 1, 3 are arranged one above the other in the composite 30, 40, can comprise at least one strain gauge 59 arranged in each case on the first component 1 or on the second component 3 for the measurement-technology detection of a variable dependent on the bending of the composite 30, 40. In this case, the controller 7 is designed to control the positioning of the actuator 13 controlled by the controller 7 via the control of the temperature control device 9, 9' corresponding to the signal S on the basis of the deflection detected by the strain gauge or gauges 59 by measurement technology.FIG. 6 shows an exemplary embodiment in which the strain gauge 59 is arranged centrally on an outer side of the second component 3. Accordingly, this strain gauge 59 is compressed in deformation states V 40(T 1>T 2) of the composite 40 caused by positive temperature differences ΔT(T 1>T 2) and stretched in deformation states V 40(T 1<T 2) of the composite 40 caused by negative temperature differences ΔT(T 1<T 2). Analogously, a strain gauge for measuring the bending of the composite 30 can also be arranged on the first component 1 and / or the second component 3 of the composite 30 illustrated in FIGS. 5 and 8.Alternatively or additionally, the measuring device can comprise e.g. at least one further sensor for metrological detection of the deformation state of the composite 10, 20, 30, 40.FIG. 5 shows, as an exemplary embodiment, a distance sensor 61 for metrological detection of a distance of the free end of the composite 30 from a predetermined reference point P 2. In the same way, a distance of the central region of the composite 40 shown in FIG. 6 from a reference point P 3 shown in dashed lines in FIG. 6 can also be determined by means of a distance sensor. These distance measurements are carried out, for example, in each case analogously to the distance measurements described in connection with the position of the actuator 13, wherein the aforementioned types of distance sensors can also be used here analogously.Analogously to the preceding exemplary embodiments, the controller 7 is designed here to control the positioning of the actuator 13 controlled by the controller 7 via the control of the temperature control device 9 corresponding to the signal S on the basis of the or each measured distance.As a further exemplary embodiment, the length L 1 of the first component 1 and the length L 2 of the second component 3 can also be determined by actuators, such as the actuators 100, 200 illustrated in FIGS. 1 to 4, for example, in which the first component 1 and the second component 3 are arranged offset parallel to one another in a plane, for example in each case by means of a distance sensor for metrological detection of a distance between the end of the respective component 1, 3 facing away from the base 5 and a reference point assigned to the respective component 1, 3. These distance measurements are also carried out, for example, analogously to the distance measurements described in connection with the position of the actuator 13, wherein the aforementioned distance sensors can also be used here analogously. In this case, the controller 7 is designed, for example, to perform the positioning of the actuator 13, which is controlled by the controller 7 via the control of the temperature control device 9 corresponding to the signal S, on the basis of a difference, corresponding to the difference in length ΔL, of the distances measured with the two distance sensors.List of reference characters100 Actuator 200 Actuator 300 Actuator 400 Actuator 500 Actuator 10 Composite 20 Composite 30 Composite 40 Composite 1 First component 3 Second component 5 Base 7 Controller 9 Temperature control device 9' Temperature control device 11 Converter 13 Actuator 15 Connection 17 Connection 19 Converter 21 First lever 23 Deflection device 25 Second lever 27 Further connection 29 Connecting piece 31 Spacer 32 Cavity 33 Insulation layer 35 Clamping device 37 Converter 39 Bearing 41 Bearing 43 Printed circuit board layer 45 Metallic layer 47 Temperature sensor 48 Temperature sensor 49 Distance sensor 51 Electrode 53 Electrode 55 Strain gauge 57 Strain gauge 59 Strain gauge 61 Distance sensor

Claims

Actuator (100, 200, 300, 400, 500) having a composite (10, 20, 30, 40) which comprises a rod-shaped first component (1) and a rod-shaped second component (3) connected at least at one end to the first component (1), wherein the first component (1) and the second component (3) have identical coefficients of thermal expansion, a controller (7) to which a signal (S) can be applied on the input side, a temperature control device (9, 9') connected to the controller (7) and which is designed to bring about a temperature difference (ΔT) which can be predefined by means of the controller (7) in accordance with the input signal (S) between a temperature (T1) of the first component (1) and a temperature (T2) of the second component (3), and a mechanical converter (11, 19, 37), which converts a property of a deformation state of the composite (10, 20, 30, 40), which deformation state is dependent on the magnitude of the temperature difference (ΔT), into a positioning, corresponding thereto, of an actuator (13) of the actuator (100, 200, 300, 400, 500), which actuator is formed as a component of the converter (11, 19, 37) or is connected to the converter (11, 19, 37).Actuator (100, 200) according to claim 1, wherein the first component (1) and the second component (3) are arranged offset parallel to each other in a plane, an end of the first component (1) is connected to an end of the second component (3) via a rigid base (5), and the converter (11, 19) converts a length difference (ΔL) between a length (L1) of the first component (1) and a length (L2) of the second component (3) dependent on the temperature difference (ΔT) into a positioning of the actuator (13) corresponding to the length difference (ΔL).Actuator (100, 200) according to claim 2, wherein the converter (11, 19) is configured as a first lever or comprises a first lever (21), wherein the first lever (21): comprises an end which forms or comprises the actuator (13), on which the actuator (13) is arranged or which is mechanically connected to the actuator (13), and comprises an end region opposite the end which is connected via a first connection (15) to a free end of the first component (1) remote from the base (5) and via a second connection (17), spaced apart from the first connection (15) along a longitudinal axis of the first lever (21), to a free end of the second component (3) remote from the base (5).Actuator (200) according to Claim 3, in which the end of the first lever (21) is connected to a first end region of a second lever (25) via a deflection device (23), the first end region of the second lever (25) is additionally connected to the base (5) via a further connection (27) spaced apart from the deflection device (23) in a direction running parallel to the longitudinal axis of the second lever (25), and the actuating element (13) is formed by a region of a second end region of the second lever (25) facing away from the deflection device (23), said region projecting perpendicularly to the longitudinal axis of the second lever (25) in a direction facing away from the first lever (21), is arranged on a region of the second lever (25) facing away from the deflection device (23), is formed by a region of the second lever (25) facing away from the deflection device (23), or mechanically connected to a region of the second lever (25) facing away from the deflecting device (23).Actuator (200) according to Claim 4, in which the second lever (25) runs parallel to the first lever (21) at the same temperature (T1, T2) of the first component (1) and of the second component (3), and / or the deflecting device (23) and the further connection (27) are elastic and / or are designed as connecting webs.Actuator (100, 200) according to Claims 2 to 5, in which the first component (1), the second component (3), the base (5), the first connection (15), the second connection (17), the further connection (27) and / or the converter (11, 19) or at least partial regions of the converter (11, 19) are formed as regions of a one-piece component or of a one-piece, single- or multilayer printed circuit board, and / or the first connection (15) and the second connection (17) are each formed as an elastic connection and / or is formed as a connecting web, the width of which is virtually smaller than a width of the first component (1) and of the second component (3).Actuator (200) according to Claims 2 to 6, in which a first strain gauge (55) connected to the controller (7) for metrological detection of a linear extent of the first component (1) is arranged on the first component (1), a second strain gauge (57) connected to the controller (7) for metrological detection of a linear extent of the second component (3) is arranged on the second component (3), and the controller (7) is designed to regulate the positioning of the actuator (13) controlled by the controller (7) via an actuation of the temperature control device (9) corresponding to the signal (S) on the basis of a difference between the linear extent of the first component (1) measured with the first strain gauge (55) and the linear extent of the second component (3) measured with the second strain gauge (57).Actuator (300, 400, 500) according to Claim 1, in which the first component (1) and the second component (3) in the composite (30, 40) are arranged one above the other and are thermally insulated from one another, and the converter (37) converts a deflection of the composite (30, 40), which deflection is dependent on the temperature difference (ΔT), into the positioning of the actuator (13) corresponding thereto.Actuator (300, 500) according to Claim 8, in which the composite (30) is freely movable apart from an end of the composite (30) fixed in its position, clamped in a clamping device (35) or mounted on a carrier, and the converter (37) is designed to convert a deflection, corresponding to the deflection dependent on the temperature difference (ΔT), of a freely movable end of the composite (30) connected to the converter (37) and opposite the fixed end into the positioning of the actuator (13) corresponding thereto.Actuator (400) according to Claim 8, in which the mutually opposite outer ends of the composite (40) are each arranged in or on a bearing (39, 41), in a bearing (41) designed as a surround or on a bearing surface serving as a bearing (39) in such a way that a central region of the composite (40) situated therebetween is freely movable, and the converter (37) is designed to convert a deflection, which corresponds to the deflection dependent on the temperature difference (ΔT), of the central region of the composite (40) connected to the converter (37) into the positioning of the actuator (13) corresponding thereto.Actuator (300, 400, 500) according to Claims 8 to 10, in which the first component (1) is thermally insulated with respect to the second component (3) by each of the two outer ends of the first component (1) being connected to one of the two outer ends of the second component (3) in each case via a spacer (31) or a spacer (31) made of a thermal insulator, of glass, plastic or ceramic, or by the first component (1) being connected to the second component (3) over its full area by an insulation layer (33) arranged between the first component (1) and the second component (3) or by an insulation layer (33) made of plastic, the composite (30, 40) being constructed from individual parts, being formed as a component produced in a 3-D printing process, being formed as a multilayer printed circuit board, or comprising two identically constructed printed circuit boards, The temperature control device (9') of which forms the first component (1) and the other forms the second component (3), and / or the temperature control device (9') comprises at least one element (E) respectively arranged between the first component (1) and the second component (3) and respectively formed as a heating and cooling element or as a Peltier element (E), wherein the or each element (E) is respectively arranged and formed in such a way that, in order to generate a temperature difference (ΔT) corresponding to the signal (S), when the temperature control device (9') or each element (E) is controlled accordingly by the controller (7), it heats simultaneously one of the two components (1, 3) adjoining it and cools the respective other component (3, 1).Actuator (400) according to Claims 8 to 11, having at least one strain gauge (59), which is arranged in each case on the first component (1) or on the second component (3) and is connected to the controller (7) and is used for detecting a variable which is dependent on the deflection of the composite (30, 40) by measurement, in which the controller (7) is designed to regulate the positioning of the actuator (13), which is controlled by the controller (7) via an actuation of the temperature control device (9) which corresponds to the signal (S), on the basis of the deflection detected by the strain gauge or gauges (59).Actuator (100, 300, 500) according to Claims 1 to 12, in which a first temperature sensor (47), which is connected to the controller (7), for measuring the temperature (T1) of the first component (1) is arranged on the first component (1), a second temperature sensor (48), which is connected to the controller (7), for measuring the temperature (T2) of the second component (3) is arranged on the second component (3), and the controller (7) is designed to be controlled in accordance with the signal (S) by means of the temperature control device (9, 9') to be effected by regulating the temperature difference (ΔT) on the basis of a difference between the temperature (T1) of the first component (1) measured with the first temperature sensor (47) and the temperature (T2) of the second component (3) measured with the second temperature sensor (48).Actuator (100, 200, 300, 400, 500) according to Claims 1 to 13, having a measuring device connected to the controller (7) for metrological detection of at least one variable dependent on the deformation state of the composite (10, 20, 30, 40) and / or at least one variable dependent on the position of the actuating element (13), wherein the controller (7) is designed to regulate the positioning of the actuating element (13) controlled by the controller (7) by means of an actuation of the temperature control device (9) corresponding to the signal (S) on the basis of the or each variable measured by the measuring device.Actuator (100, 200, 300, 400, 500) according to Claim 14, in which the measuring device comprises: a distance sensor (49), a capacitive distance sensor, a magnetic distance sensor or an optical distance sensor for metrological detection of a distance of the actuator (13), which is dependent on the positioning of the actuating element (13), from a predefined reference point (P1), and / or comprises at least one distance sensor (61), a capacitive distance sensor, a magnetic distance sensor or an optical distance sensor for metrological detection of a variable of the composite (10, 20, 30, 40), which variable is dependent on the deformation state of the composite (10, 20, 30, 40).Actuator (100, 200, 300, 400) according to Claims 1 to 15, in which the temperature control device (9) comprises at least one element (E1) arranged on the first component (1), comprises at least one element (E2) arranged on the second component (3) or comprises at least two elements (E1, E2), of which at least one is arranged on the first component (1) and at least one is arranged on the second component (3), and the or each element (E1, E2) of the temperature control device (9) is in each case designed as an element which can be controlled by means of the controller (7) and can be operated as a heating element and / or as a cooling element.Actuator (100, 200, 300, 400, 500) according to Claims 1 to 16, in which the first component (1) and the second component (3) are of the same length at a predetermined reference temperature, and / or each have: a base surface having a length of 10 mm to 100 mm and a width of 1 mm to 10 mm, and / or have a thickness of 0.5 mm to 3 mm running perpendicular to the base surface, is formed as a single-layer or multilayer printed circuit board or as a printed circuit board region of a single-layer or multilayer printed circuit board, and / or is formed as a multilayer component which comprises at least one printed circuit board layer (43) made of a non-metallic printed circuit board material and at least one metallic layer (45) made of a metal or made of copper.

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