TW201306336A - Multi-layer composite having electroactive layers - Google Patents

Abstract

The invention relates to a multi-layer composite (2, 2.1, 2.2, 18) comprising at least two electroactive layers (4, 6) positioned between a first electrically conductive layer (12) and a second electrically conductive layer (14), wherein at least one electrically conductive sub-layer (8) is positioned between the at least two electroactive layers (4, 6), and wherein at least one of the at least two electroactive layers (4, 6) is a piezo layer (6), wherein at least one other of the at least two electroactive layers (4, 6) is a dielectric elastomer layer (4).

Description

Multilayer composite with electroactive layer

The present invention relates to a multilayer composite comprising at least two electroactive layers between a first electrically conductive layer and a second electrically conductive layer; wherein at least one of the electrically conductive sublayers is at least two electrically activated Between the layers; and at least one of the at least two electroactive layers is a piezoelectric layer. The invention is also related to an electromechanical transducer device comprising such a multilayer composite and related to a method of making a multilayer composite.

Plastic composites are used in a wide variety of applications. For example, suitable multilayer composites are used as packaging materials, insulating materials or building materials. In addition to this conventional use, multilayer composites are being used as active components in sensing applications or for energy recovery or energy conversion known as energy extraction.

For example, World Patent Publication No. 2010/066347 A2 discloses multilayer composites having a plurality of piezoelectric layers, in other words, the piezoelectric layers are fabricated from piezoelectric materials. Piezoelectric materials can be used to linearly convert mechanical force changes acting on the multilayer composite into electrical signals. The piezoelectric layer is suitable for sensor application or energy extraction because of their ability to convert mechanical forces into electrical quantities such as current, voltage or energy.

Multilayer composites are now used, for example, in structural pressure sensors for keyboards or trackpads, acceleration sensors, microphones, speakers, ultrasonic transducers, for medical engineering, marine engineering, or for material testing.

A high-frequency transmitter having a piezoelectric element as a converter device is known, for example, from the European patent EP 1 312 171 B1. The mechanical force changes acting on the piezoelectric element here are converted into electrical energy and used for autonomous operation of the high frequency transmitter.

However, a conventional disadvantage is that although a multilayer composite of piezoelectric layers having a high voltage constant is suitable for sensor applications and is suitable for energy extraction, the possible stroke is too small and the corresponding piezoelectric layer is only limitedly suitable. For the launcher application.

Accordingly, it is an object of the present invention to provide a multilayer composite that is suitable not only for inductors and energy extraction applications but also for actuator applications.

In accordance with a first aspect of the invention in a multilayer composite, the above-described derivation and recited objectives are achieved, the multilayer composite comprising at least two electroactive layers between the first electrically conductive layer and the second electrically conductive layer. Wherein at least one conductivity sublayer is between the at least two electroactive layers; and wherein at least one of the at least two electroactive layers is a piezoelectric layer; wherein at least one of the at least two electroactive layers A dielectric elastomer layer.

In accordance with the teachings of the present invention, in accordance with the teachings of the present invention, the functions of the inductor, actuator, and energy extraction are integrated into a single multilayer composite in accordance with the present invention by at least two different types of electroactive layers.

The piezoelectric layer can be formed, for example, from a suitable piezoelectric polymer and can be a piezoelectric polymer film. According to a preferred embodiment, The piezoelectric layer can be a ferroelectret layer, such as a ferroelectric electret film. The piezoelectric layer can have sustained piezoelectric properties. These can be produced, for example, by charging or polarizing the piezoelectric layer. With a high piezoelectric constant, the piezoelectric layer can be used in particular for a sensor application and/or for energy extraction. The piezoelectric layer can have, for example, a piezoelectric constant of up to 1000 pC/N.

The multilayer composite according to the invention further comprises at least one dielectric elastomer layer. The dielectric elastomer layer preferably has a relatively high dielectric constant. Furthermore, the dielectric elastomer layer preferably has a low mechanical hardness. These properties result in extension values as high as about 300%. The dielectric elastomer layer can be used in particular for a starter application.

At least one of the electrically conductive sublayers is between the piezoelectric layer and the dielectric elastomer layer. A sublayer is understood to mean that the electrically conductive material is only partially present between at least two electroactive layers. For example, a structural or segmented layer can be formed. It should be understood that the layer may also be a full layer.

Furthermore, an electrically conductive layer is anchored on the top side of the multilayer composite and an electrically conductive layer is positioned on the underside of the multilayer composite.

The electrically conductive layer can in particular be designed as an electrode. It should be understood that the underside or top side may only be partially coated with an electrically conductive layer.

An electrically conductive layer may preferably be formed from a material selected from the group consisting of metals, metal alloys, electrically conductive oligomers or polymers, electrically conductive oxides, and/or polymers filled with electrically conductive fillers.

According to the invention of at least one dielectric elastomer layer and at least one piezoelectric layer, the specific properties of the individual layer types can be combined in a multilayer composite. A hybrid and compact multilayer composite with sensor, actuator and energy extraction capabilities is obtained.

Assuming that at least one piezoelectric layer and at least one dielectric elastomer layer are incorporated, the multilayer composite can in principle have a large number of electroactive layers. In accordance with a first embodiment of the multilayer composite of the present invention, at least one other dielectric layer can be positioned between the first electrically conductive layer and the second electrically conductive layer. More mechanical energy can be converted into electrical energy, for example by the provision of two or more piezoelectric layers. The piezoelectric layers can be formed from the same or different materials. They may preferably be a ferroelectric electret layer.

Additionally or alternatively, at least another dielectric elastomer layer can be positioned between the first electrically conductive layer and the second electrically conductive layer. In a starter application, the possible thickness variations of the multilayer composite can be adjusted and in particular increased. It should be noted that in the case of a plurality of electroactive layers, an electrically conductive layer may preferably be at least partially located between all adjacent layers.

The piezoelectric layer can be designed as a foamed polymer film or as a multilayer system comprising a polymeric film or polymer fiber and can comprise a porous hollow structure. Still further, in accordance with a preferred embodiment, the piezoelectric layer can be formed from a polymeric layered structure. The polymeric layered structure can include voids. For example, the cavity contains a gas selected from the group consisting of nitrogen, nitrous oxide, and/or sulfur hexafluoride. The structural piezoelectric layer can comprise at least two closed outer layers and, for example, a perforated or perforated intermediate layer.

As the piezoelectric layer is electrically charged or polarized, differently polarized charges can be distributed on opposite surfaces of the cavity. Each cavity can form a dipole. If a mechanical force is applied to a piezoelectric layer, the dipole size and hence the dipole moment change. The flow of current is generated between the two electrodes, which are attached to the two surfaces of the piezoelectric layer. Piezoelectric layers with corresponding polymer layer structures are particularly suitable for sensor applications and Suitable for energy extraction.

According to another embodiment of the multilayer composite of the present invention, the piezoelectric layer may advantageously comprise a substance selected from the group consisting of polycarbonate, perfluorinated or partially fluorinated polymers and copolymers, and polytetrafluoroethylene. , fluoroethylene propylene, perfluorinated alkoxyethylene, polyester, polyethylene terephthalate, polyethylene naphthalate, poly phthalimide, polyether phthalimide, polyether, poly (a Group of methyl acrylate, cyclic olefin polymer, cyclic olefin copolymer and/or polyolefin.

Still further in accordance with a preferred embodiment of the present invention, the dielectric elastomer layer may comprise a substance selected, for example, from the group comprising polyurethane elastomers, polyoxyxides, and/or acrylate elastomers.

Another aspect of the invention is an electromechanical transducer device comprising the multilayer composite described above. The converter device according to the invention can be specially constructed to convert the mechanical force acting on it into electrical energy or into an electrical signal and to change the geometry, in particular an electric field, depending on the application of the electronic signal. As has been described, in an electromechanical transducer device having a multilayer composite as described above, the actuator, sensor and energy extraction functions are integrated into a single device. It should be understood that an electromechanical transducer device can have two or more multilayer composites.

In accordance with a first embodiment of the electromechanical transducer device of the present invention, the multilayer composite can be coupled to a user interface such that the mechanical force converted to the user interface changes to an electrical signal. In other words, a sensor function can be provided. The activation of the user interface changes the shape of the multilayer composite

The change in shape of the multilayer composite produces a voltage that can be detected, for example, by appropriate means.

Additionally or alternatively, the multilayer composite can be coupled to a user interface such that the mechanical force that can be converted to act on the user interface changes to electrical energy. The user interface can in particular be a surface, such as a button of a switch, which can be activated by a user. The user interface can be connected to a multi-layer composite, in particular an electrode of the multilayer composite, such that forces acting on the user interface also act on the multilayer composite, mechanical forces being varied, for example pressure from the user's fingers can be converted For electrical energy or converted to an electrical signal.

In accordance with another embodiment of the electromechanical transducer device of the present invention, a circuit configuration for electrically connecting the multilayer composite is provided to further process the generated electrical signals or to use the generated electrical energy. The circuit configuration can be connected to the electrically conductive layer in an appropriate manner. The circuit configuration can have analog and/or digital components to further process an electronic signal, such as a voltage or current and/or at least temporarily store electrical energy. For example, a suitable capacitive element can be provided as a storage device in a circuit configuration. The circuit configuration can be constructed in such a way that a voltage can be applied to at least some of the electrodes of the multilayer composite. It should be understood that the circuit configuration can be designed in accordance with the functionality required of the electromechanical converter device.

According to a preferred embodiment of the electromechanical device of the present invention, the supply circuit configuration can be operated autonomously by converting mechanical energy into electrical energy. In other words, the circuit configuration can be operated exclusively using mechanical forces acting on the device, in particular independent of the additional power supply. It is necessary to have no additional energy storage device as an additional energy supply. However, it should be understood that the energy storage device can provide storage of electrical energy as a result of changes in mechanical forces, particularly temporary. Store. For example, the generated electrical energy can be collected in a storage device, such as a capacitor, ultracapacitor, and/or battery. This may be necessary if multiple starts are not required and insufficient energy may be provided by a single start of the electromechanical conversion device. Once sufficient energy is collected, the desired action can be performed.

Additionally, the circuit configuration can include a power supply. If the electrical energy generated by the multilayer composite is insufficient to perform one or more desired actions, an additional power supply, such as in the form of an energy storage device, may be necessary. For example, energy may be insufficient because of the specified and compact and especially planar design of the multilayer composite and/or because of the function to be performed.

The circuit configuration can preferably be constructed to allow the circuit configuration to be converted from electrical energy to an operational state by mechanical energy conversion. In other words, the circuit configuration is awakened from a sleep state. It can then supply energy from an energy storage device such as a battery. The circuit configuration can be (automatically) moved back to the idle state after performing at least one action. In this way, the life of the energy storage device can be effectively extended. For example, a life of 20 years can be achieved (for example, using a lithium-manganese dioxide battery). Circuit configurations including processors and storage devices, etc., can be manufactured on a larger scale, which are low maintenance and have a long life.

According to an advantageous embodiment, the circuit arrangement may comprise a transmission element for transmitting a signal. In particular, this can be a transmission element that sends a wireless signal such as a short pulse or packet. For example, the transmission element can have an antenna configuration. The wireless signal can be delivered, for example, to a remote receiver. For example, the receiver can include an actuator and can control a consumer, such as a heater or a light Optical device.

For example, the wireless signal may further have a unique identification code that causes the transmitter (in other words, the electromechanical transducer device) to be identified. A corresponding device can be used, for example, in a security system or a personal monitoring system. An operator can be located by the identification code.

An action can be triggered by mechanical pressure in the conversion device. However, especially if the converter device has a very short actuator stroke, the user cannot confirm whether his touch has actually been logged in. In order to provide feedback that the activation of the electromechanical transducer device has been truly triggered by the user, the multilayer composite of the electromechanical transducer device can be designed to impart a tactile feedback via the user interface in accordance with a preferred embodiment. For example, tactile feedback is imparted by vibration and/or (reverse) pressure.

In accordance with another preferred embodiment of the electromechanical transducer device of the present invention, for tactile feedback, a voltage can be applied to the at least one dielectric elastomer layer in an elastic layer of at least 0.1 microns and preferably at least 10 microns. The thickness variation is produced at a predefinable frequency. An electric field, particularly an alternating electric field, can be applied to at least two electrodes on the surface of at least one of the dielectric elastomer layers. It has been recognized that if the electromechanical transducer device is activated with the user's finger, for example, sufficient haptic feedback is achieved depending on thickness and frequency changes. It has been particularly recognized that in the frequency range between 200 and 250 Hz the human finger is at the most sensitive perceptual threshold of about 0.1 micron. Larger variations in thickness can be obtained in other frequency ranges, for example, by providing a plurality of dielectric elastomer layers. Even a short starter stroke allows a user to receive a good tactile feedback.

The user interface can be designed to trigger one or more actions One section. According to another embodiment, the user interface can include a first segment that triggers the first action and at least a second segment that triggers a second action. For example, each segment can be connected to a separate multilayer composite to achieve different triggering actions. It should be understood that operator control can also be divided into three to four segments, for example to perform additional actions.

According to a further embodiment the electromechanical converter device can be an inductor device, such as a switching device. For example, the electromechanical transducer device can be a tactile sensor, a planar sensor, or a floor sensor.

A tactile sensor of the conventional design may preferably be formed with two or more piezoelectric layers. This allows, for example, an actuator stroke of up to about 2 mm. Again, two or more piezoelectric layers allow, for example, a force of up to about 5 Newtons. By mechanical and electronic adjustment, a sufficiently large, temporarily stored electrical energy can be generated using, for example, a starter stroke of up to about 2 mm and a force of up to about 5 Newtons, which can be operated by an auxiliary autonomous tactile sensor that utilizes this electrical energy. For example a wireless rocker button.

With a visual appeal and especially a planar design, the planar sensor can have exactly one piezoelectric layer and one dielectric elastomer layer. A starter stroke of less than 500 microns is available in this planar sensor (not detectable). In particular, by means of a dielectric elastomer layer, tactile feedback can be provided as a confirmation operating plane sensor. In addition to haptic feedback, a feedback signal can be transferred from the activated component to the user, for example, a wireless signal can be transmitted.

Another possible application of electromechanical devices is a floor sensor, such as a smart floor element (smart carpet). The device may for example be formed in the form of a tile, for example it may have a surface area of 100 cm ² or more. The tile may have a depth of about 1 mm. This floor element can in particular have a multi-layer piezoelectric layer. Approximately 100 Newtons and more operating forces are possible. More than 300 microjoules of energy can be obtained in this way. In addition to the energy recovery function, the multilayer composite can be used as a sensing element to position an operator, for example, on the floor.

A tactile sensor, plane sensor or floor sensor can be used, for example, in a building automation system or in personal monitoring, such as patient monitoring. For example, under mechanical load, a corresponding sensor can deliver a signal to one or more receivers. The received signal can be processed and an action (eg, an alarm) can be triggered, or a consumer can be activated or deactivated.

For example, a large number of floor sensors can be provided in a building and a unique identification code is assigned to each sensor. In a surveillance system, the user can be located by a process in which when a sensor is activated it delivers its identification code to a processing device that positions the sensor and thus the operator The location is inferred.

If the electronic output variable is, for example, reproducible and provides long-term stability and correlates with the weight of a person or object, the measured "weight" can be integrated into a wireless camera to provide information about a person or vehicle on a smart floor. Additional message. This has led to interesting applications such as in elderly medicine and in all forms of ambient assisted living (AAL).

A touch sensor can also be used for a key, such as a car key or a door key, for example to unlock the corresponding device by wireless. For example, a car key can be used autonomously.

It should be understood that the multilayer composite according to the present invention or the electromechanical device according to the present invention can also be used for other applications, such as in a keyboard or touch pad, an acceleration sensor, a microphone, a speaker structure, according to another variation. Sexy instrumentation in medical engineering, marine engineering applications or material testing in ultrasonic transducers. The use as a general mechanical pressure sensor is also possible in automation engineering and automotive engineering, in the latter case, for example as a steering wheel sensor or a seat sensor.

The highly sensitive materials that are preferably used also allow an inductor to be used under a plate that is only slightly deformable but otherwise rigid. This feature is used, for example, for a tamper-resistant keypad with a thin steel plate, for example manufactured by Screentec (Finland), but can for example also be used in the aforementioned "smart floor" sensor applications.

A further aspect of the invention is a method of making a multilayer composite having at least two electroactive layers, the at least two electroactive layers being between a first electrically conductive layer and a second electrically conductive layer, at least one of which The electrically conductive sublayer is between the at least two electroactive layers, wherein at least one of the at least two electroactive layers is a piezoelectric layer, and wherein at least one of the at least two electroactive layers is An electroelastic layer, the method comprising the steps of: providing at least one piezoelectric layer; providing at least one dielectric elastomer layer; connecting the piezoelectric layer to the dielectric elastomer layer; wherein at least one is connected before connecting the piezoelectric layer to the dielectric elastomer layer The electrically conductive sublayer is laid down on the piezoelectric layer and/or the dielectric elastomer layer.

The provided piezoelectric layer may, for example, preferably be at least partially provided with an electrically conductive layer on both sides thereof. The dielectric elastomer layer can preferably be directly connected Connected to at least one of these electrically conductive layers. In a further step, the dielectric elastomer layer may be at least partially provided with an additional electrically conductive layer. It will be appreciated that the dielectric elastomer layer may preferably be first coated with an electrically conductive layer on both sides thereof. The piezoelectric layer can then be coated.

It will further be appreciated that in accordance with a further variation of the invention, the additional piezoelectric layer and/or the additional dielectric elastomer layer may be positioned in a further step. For example, a multilayer composite comprising at least one piezoelectric layer and a dielectric elastomer layer between the two electrically conductive layers can be connected in series with a multilayer composite of the same construction.

Still further, in accordance with a first embodiment of the method of the present invention, a dielectric elastomer layer or a piezoelectric layer can be laminated to the electrically conductive layer. This leads to particularly good contact between the corresponding layers in a simple manner.

In accordance with a preferred embodiment of the method of the present invention, the dielectric elastomer layer or piezoelectric layer can be printed at least in part by an electrically conductive layer. For example, a structural electrode can be printed. A printing method can be implemented in a simple manner. In particular, it is possible to mass-produce a multilayer composite at a high production rate.

A large number of possibilities exist for beautifying and further developing the multilayer composite according to the invention, the electromechanical conversion device according to the invention and the method for producing a multilayer composite according to the invention. In this regard, the first relates to the dependent items attached to the independent items, and the second relates to the description of the embodiments in conjunction with the drawings.

Figure 1 shows a schematic view of a first embodiment of a multilayer composite 2 in accordance with the present invention. The illustrated multilayer composite 2 comprises two electroactivation Layers 4 and 6.

The electroactive layer 4 is a dielectric elastomer layer 4. The dielectric elastomer layer 4 advantageously has a relatively high dielectric constant. Furthermore, the dielectric elastomer layer 4 advantageously has a low mechanical rigidity. This results in a possible extension of up to approximately 300%. The dielectric elastomer layer 4 can be used in particular for actuator applications.

The second electroactive layer 6 is formed as a piezoelectric layer 6. The illustrated piezoelectric layer can be formed, for example, from a suitable piezoelectric polymer and can be, for example, a piezoelectric polymer film or a ferroelectret film. The illustrated piezoelectric layer 6 has a polymer layered structure. The polymer layered structure has (intentionally) incorporated voids 10.

In order to generate the voids 10, for example, a flat polymer layer and a corrugated polymer layer may be provided, which are connected to each other in the wave grooves. In a further embodiment of the piezoelectric layer 6, the two flat polymer layers may be joined by ribs to form the voids 10.

The piezoelectric layer 6 can be electrically charged before the piezoelectric layer 6 is placed in the multilayer composite 2. Electrical charging or polarization can be performed, for example, by direct charging or corona discharge. Charging or polarization imparts sustained piezoelectric properties to the piezoelectric layer 6. The piezoelectric layer 6 can be used in particular for a sensor application and/or energy extraction.

FIG. 1 further concludes that at least one of the electrically conductive sub-layers 8 is between the dielectric elastomer layer 4 and the piezoelectric layer 6. It will be appreciated that multiple layers and/or a full layer may also be positioned. The electrically conductive sub-layer 8 is preferably connected to the dielectric elastomer layer 4 and/or the piezoelectric layer 6 in opposite directions. The electrically conductive sub-layer 8 can in particular be designed as an electrode. For example, it can be from a metal, a metal alloy, a conductive low polymer or polymer, a conductive oxide, and/or The conductive filler-filled polymer forms an electrode.

Furthermore, two electroactive layers 4 and 6 are located between the two additional electrically conductive layers 12 and 14.

The electrically conductive layer 14 is applied on top of the piezoelectric layer 6 and in particular covers the entire surface of the piezoelectric layer 6. Conductive layer 12 can be coated on top of dielectric elastomer layer 4. For example, a split layer 12 can be provided. Conductive layers 12 and 14 are also preferably formed on a metal basis.

The hybrid multilayer composite 2 comprising at least one dielectric elastomer layer 4 and at least one piezoelectric layer 6 is particularly characterized in that three functions can be combined and obtained in a single multilayer composite. In particular, the functions of the actuator, energy extraction and inductor are provided by a single multilayer composite.

However, when an electric field is applied in a dielectric elastomer layer, the surface area of the dielectric elastomer layer changes, and the thickness of the ferroelectric electret in a ferroelectric electret film substantially changes. The configuration of the two types of electroactive layers means that a change in shape only in the direction X perpendicular to the layers 4 and 6 can be achieved. Therefore, the thickness of the multilayer composite 2 can be changed, in other words, increased or decreased, and it is impossible to have a substantial change in shape in the other direction. It should be noted that shape changes in the other direction are permissible depending on the actual application.

Furthermore, Figure 2 shows another embodiment of a multilayer composite 2.1 in accordance with the present invention. As can be inferred from Figure 2, the multilayer composite 2.1 has the two-layer composite 2 according to Figure 1. In particular, the multilayer composites 2 are arranged in a mirror-symmetrical arrangement on top of each other. It should be understood that only one conductive layer 12 or two layers of composite 2 can be provided. The conductive layers 12 may be connected to each other to form an electrically conductive layer 12.

Figure 3 shows a third embodiment of a multilayer composite 2.2 in accordance with the present invention. The multilayer composite 2.2 comprises, for example, a tandem multilayer composite 2.1 according to FIG. It should be understood that further concatenation is possible. It should also be understood that the two layers 14 which provide only one layer of 14 or multi-layer composite 2.1 may be joined to each other to form a layer 14.

It should also be understood that in accordance with other variations of the present invention, a composite layer can be constructed in any other form provided that at least one dielectric elastomer layer and at least one piezoelectric layer are provided. For example, two or more piezoelectric layers plus one (or more) elastomer layers may be provided.

Figure 4 shows a simplified view of an embodiment of an electromechanical transducer device 16 in accordance with the present invention. For example, the electromechanical transducer device 16 can be designed as a switch, such as a tactile sensor, a planar sensor, or as a smart floor element. In particular, the converter device 16 can be used in a building automation system. Thus, the transducer device 16 can be used to control heaters, lighting, shading devices, etc., or for use in elderly medicine (activity or fall detection) or for use in security technology.

The electromechanical transducer device 16 includes a multilayer composite 18 which is not shown in detail for better illustration. For example, multilayer composites 2, 2.1 or 2.2 according to Figures 1 to 3 can be used.

The design of the multilayer composite 18 is particularly dictated by the application of the electromechanical converter device 16.

A tactile sensor of conventional design may preferably be formed with two or more piezoelectric layers 6. This allows the actuator stroke to be, for example, up to about 2 mm. Furthermore, two or more piezoelectric layers 6 mean that mechanical forces, for example up to about 5 Newtons, can be converted to electricity.

In contrast, a planar sensor can have as few layers as possible and/or layers of low thickness. For example, the planar sensor can have a piezoelectric layer and a dielectric elastomer layer. In such a planar sensor (undetectable) an actuator stroke of less than 500 microns can be achieved. The planar sensor can be activated immediately with a less than 1 Newton. In particular, by applying a voltage to the dielectric elastomer layer, haptic feedback can be provided as a confirmation of the operation of the planar sensor. In addition to the haptic feedback, the feedback signal can be transmitted from the activated component to the user. For example, this can occur via a wireless signal.

Yet another possible application of the converter device 16 is a floor sensor such as a smart floor element. The converter device 16 can be formed, for example, in the form of a tile, for example, the tile can have an area of 100 cm ² or more. Additionally, the tiles may have a depth of approximately 1 millimeter. This bottom plate element can in particular have multiple piezoelectric layers. 100 Newtons and greater operating force are possible. In this way, an energy level in excess of 300 microjoules can be obtained.

The multilayer composite 18, and in particular the top electrode, can be connected to a user interface 20. The user interface is understood to be a surface that can be activated by a user, in other words, for example, the pressure applied to it to produce the desired function.

In principle, the user interface 20 can be designed in any way. The user interface 20 can have a first section 20.1 and a second section 20.2, which can be, for example, visually distinct from each other. The first section 20.1 can provide a first action and the second section 20.2 can provide a second action. It should be understood that more than just two segments and more than one segment may also be provided.

A circuit configuration 22 can be coupled to the multilayer composite 18. Circuit configuration 22 can connect the electrodes of multilayer composite 18. Circuit configuration 22 and multilayer composite 18 can be integrated into a housing (not shown) or in a modular configuration. The modular construction, for example, allows for a flexible combination of different components to achieve different functions.

Circuit configuration 22 can be installed to generate an action based on an electronic signal that is attributed to the activation of the electromechanical converter device. For example, a delivery element 24 can be disposed in circuit configuration 22. When receiving an electrical signal from the multilayer composite 18, the transmission component 24 can transmit a message. In particular, wireless signals can be sent out. It should be understood that the wired interface can also be provided as a substitute or additive.

The information sent can be received by one or more receivers 28.1, 28.2. The receivers 28.1, 28.2 can include an initiator or a connectable initiator to control the consumer (not shown) in accordance with the received information. As described above, for example, a heater or the like can be controlled. Furthermore, the received information, such as an identification code, can cause the operator's location to be inferred.

The possibility of supplying line energy 22 to generate a wireless signal includes, for example, the use of mechanical forces on the user interface 20. As mentioned above, the piezoelectric layer 6 is particularly suitable for energy extraction. In the tactile sensor described above, for example, mechanical energy converted into electrical energy may be sufficient to deliver a wireless signal. In particular, for example, a capacitor, an ultracapacitor or a battery can be used to collect the generated electrical energy and temporarily store it. This action can be performed once a sufficient amount of energy is stored to perform an action. An autonomous electromechanical transducer device 16 can be provided.

Circuit configuration 22 can optionally include an energy storage device 26 (eg battery). An energy storage device 26 may be necessary, particularly if the electrical energy generated by the mechanical force change is insufficient for the autonomous operating system of the circuit configuration 22. This is the case where a planar sensor can be produced, for example, it can only comprise a piezoelectric layer 6, for example. For example, considering the available space, approximately 100 pJ (picojoules) can be generated. This energy can be used to shift circuit configuration 22 from an idle state to an operational state, in other words to wake it up. Circuit configuration 22 can then be powered by energy storage device 26 to perform at least a desired function. The circuit configuration is preferably automatically transferred back to the idle state.

The standby current draw in such an electromechanical converter device 16 is close to the self-discharge of the energy storage device 26. Arousal energy can be specifically produced by mechanical force changes. For example, a lifetime of more than 20 years can be achieved (eg, using a lithium/manganese dioxide battery).

An energy storage device may be necessary if the operation of the circuit arrangement requires more energy than can be provided by mechanical force changes. It should be understood that the circuit configuration may further include elements such as a processor, storage device or interface.

The circuit configuration 22 can be further connected to at least the electrodes of the dielectric elastomer layer 4 such that an electric field system can be supplied to an actuator application to produce a change in thickness. For example, a haptic feedback can be given to the user by the actuator function of the electromechanical transducer device 16. Therefore, an alternating electric field having a frequency of 200 to 250 Hz can be generated. The variation in thickness of the electromechanical transducer device 16 of at least 0.1 micron, preferably 10 micron, can be produced, for example, by this alternating electric field. It has been confirmed that these parameter values are particularly sensitive to human fingers.

Figure 5 shows a method of making a multilayer composite in accordance with the present invention A first embodiment of the invention.

In the first step 601, a piezoelectric layer 6 can provide, for example, a ferroelectric electret film. In a second step 602 a conductive sub-layer 8 can be applied to at least one side of the piezoelectric layer 6, for example by coating. The dielectric elastomer layer 4 then provided in step 603 can be laid over at least one electrically conductive layer 8 by lamination. The multilayer composite 2.1 having the piezoelectric layer 4 and the dielectric elastomer layer 6 can be produced in a simple manner.

It should be understood that the manufacturing steps can in principle be arbitrary. In particular, a dielectric elastomer layer 4 is optionally provided in the first step, which may then first provide an electrically conductive layer 8. A piezoelectric layer 6 can then be provided.

Figure 6 shows another embodiment of a method of making a multilayer composite in accordance with the present invention.

In a first step 701, a piezoelectric layer 6, such as a ferroelectric electret film, may first be provided.

In a second step 702, the piezoelectric layer 6 can preferably be coated on both sides with an electrically conductive layer 8, 14. In particular, the piezoelectric layer 6 can be applied to the entire surface on both sides. In addition to the entire surface coated outer piezoelectric layer, only a portion of the electrically conductive layer 8 or 14 may be coated separately. A structural electrode can be fabricated. In particular, active and passive zones can be generated in this way.

The electroelastic layer 4, in particular an elastomeric film, can then be laminated on the top or bottom electrically conductive layers 8, 14 in step 703.

It is preferred that the dielectric elastomer layer 4 is (only) partially laminated. This can be advantageous in particular because the dielectric elastomer layer 4 and the piezoelectric layer 6 have different extension values.

In the next step 704, the intermediate electro-elastic layer 4 can be A preferably segmented electrically conductive layer 12 (e.g., a structured electrode) is sequentially printed on its top side. A structural electrode is characterized in particular by passive and active regions. In the subsequent operation of the multilayer composite 2 it can be isolated from the ground point in this way.

Furthermore, the multilayer composite 2 can be joined to the multilayer composite 2 of the same construction, in particular by lamination in a mirror-symmetrical configuration (step 706). For example, layers 12 can be connected to each other.

The multilayer composite can be selectively fabricated by laminating two or more of these multilayer composites 2.1. For example, the two-layer composite 2.1 can be connected in series by stacking, bonding or laminating.

The multilayer composite that has been fabricated in a further step 708 can produce a desired shape in a predefinable size. For example, a separate multilayer composite can be stamped out.

The multilayer composites produced in the further methods can be electrically connected to a circuit configuration. In particular, the circuit arrangement can be connected to an electrically conductive layer designed as an electrode.

It should also be understood herein that in accordance with other variations of the invention, there may be steps in a different order and this may be particularly in accordance with particular embodiments of the multilayer composite. For example, two identical layers can be connected to each other before they are layered.

2, 2.1 2.2, 18‧‧‧ multilayer composite

4, 6‧‧‧Electrical activation layer (dielectric elastomer layer, piezoelectric layer)

8‧‧‧ Conductance sublayer

10‧‧‧ hole

12‧‧‧First Conductive Layer

14‧‧‧Second Conductive Layer

16‧‧‧Mechanical converter device

20‧‧‧User interface

20.1‧‧‧First section

20.2‧‧‧Second section

22‧‧‧Circuit configuration

24‧‧‧Conveying components

26‧‧‧Power supply (energy storage device)

28.1, 28.2‧‧‧ Receiver

1 is a schematic view showing a first embodiment of a multilayer composite according to the present invention; and FIG. 2 is a schematic view showing a second embodiment of a multilayer composite according to the present invention; Figure 3 is a schematic view showing a third embodiment of a multilayer composite in accordance with the present invention; Figure 4 is a schematic view showing a first embodiment of an electromechanical transducer device in accordance with the present invention; A flow chart of a first embodiment of a method of making a multilayer composite; and Figure 6 shows a flow chart of a second embodiment of a method of making a multilayer composite in accordance with the present invention.

2‧‧‧Multilayer composite

4‧‧‧dielectric elastomer layer

6‧‧‧Piezoelectric layer

8‧‧‧ Conductance sublayer

10‧‧‧ hole

12‧‧‧First Conductive Layer

14‧‧‧Second Conductive Layer

Claims (15)

A multilayer composite (2, 2.1, 2.2, 18) comprising: at least two electroactive layers (4, 6) between a first electrically conductive layer (12) and a second electrically conductive layer (14); a conducting sublayer (8) between the at least two electroactive layers (4, 6); and wherein at least one of the at least two electroactive layers (4, 6) is a piezoelectric layer (6) It is characterized in that at least one of the at least two electroactive layers (4, 6) is a dielectric elastomer layer (4). The multilayer composite (2, 2.1, 2.2, 18) of claim 1, wherein: at least one additional piezoelectric layer (6) is located in the first electrically conductive layer (12) and the second conductance Between layers (14); and/or at least one additional dielectric elastomer layer (4) is located between the first electrically conductive layer (12) and the second electrically conductive layer (14). The multilayer composite (2, 2.1, 2.2, 18) according to any one of claims 1 to 2, wherein the piezoelectric layer (6) is a ferroelectret layer. The multilayer composite (2, 2.1, 2.2, 18) according to any one of claims 1 to 3, wherein: The piezoelectric layer (6) comprises a material selected from the group consisting of polycarbonate, perfluorinated or partially fluorinated polymers and copolymers, polytetrafluoroethylene, fluoroethylene propylene, perfluorinated alkoxyethylene, Polyester, polyethylene terephthalate, polyethylene naphthalate, polyimide, polyether phthalimide, polyether, poly(methyl) acrylate, cyclic olefin polymer, ring The group of olefin copolymers and/or polyolefins, and/or the dielectric elastomer layer (4) comprises a material selected from the group consisting of polyurethane elastomers, polyoxyxides and/or acrylate elastomers. . An electromechanical transducer device (16) comprising a multilayer composite (2, 2.1, 2.2, 18) according to any one of claims 1 to 4. The electromechanical transducer device (16) according to claim 5, wherein the multilayer composite (2, 2.1, 2.2, 18) is connected to a user interface (20) such that a user acts on the user The change in mechanical force on the interface (20) can be converted to an electrical signal and/or converted to electrical energy. The electromechanical transducer device (16) of any of claims 5 to 6, wherein a circuit configuration (22) is provided to connect the multilayer composite (2, 2.1, 2.2, 18). The electromechanical transducer device (16) according to any one of claims 5 to 7, wherein the circuit configuration (22) is autonomously operable by mechanical energy conversion into electrical energy; or the circuit configuration (22) A power supply (26) is included, wherein the circuit configuration (22) can be moved from an idle state to an operational state by the mechanical energy being converted into electrical energy. The electromechanical transducer device (16) according to any one of claims 5 to 8, wherein the circuit arrangement (22) comprises a transport element (24) for transmitting a signal. The electromechanical transducer device (16) of claim 9, wherein: for a haptic feedback, applying a voltage to at least the dielectric elastomer layer (4) such that the multilayer composite of at least 0.1 micron ( 2. A thickness variation of 2., 2.2, 18) is produced at a predefinable frequency. The electromechanical transducer device (16) according to any one of claims 5 to 10, wherein the user interface (20) comprises a first segment (20.1) and at least a second segment ( 20.2), wherein the first segment (20.1) is used to trigger a first action and the second segment (20.2) is used to trigger a second action. The electromechanical transducer device (16) according to any one of claims 5 to 11, wherein the electromechanical transducer device (10) is a mechanical pressure sensor, in particular a tactile sensor, a plane Sensor or a floor sensor. A method of producing a multilayer composite (2, 2.1, 2.2, 18) having at least two electroactive layers (4, 6), the second electroactive layer ( 4, 6) is located between a first electrically conductive layer (12) and a second electrically conductive layer (14), wherein at least one electrically conductive sublayer (8) is located between the at least two electroactive layers (4, 6) Wherein at least one of the at least two electroactive layers (4, 6) is a piezoelectric layer (6), and wherein at least one of the at least two electroactive layers (4, 6) is one a dielectric elastomer layer (4), the method comprising: providing the at least one piezoelectric layer (6); providing the at least one dielectric elastomer layer (4); connecting the piezoelectric layer (6) to the dielectric elastomer layer ( 4); wherein the at least one electrically conductive sublayer (8) is laid onto the piezoelectric layer (6) and/or the dielectric before connecting the piezoelectric layer (6) to the dielectric elastomer layer (4) Elastomer layer (4). The method of claim 13, wherein the dielectric elastomer layer (4) or the piezoelectric layer (6) is laminated to the conductor layer (8). According to any one of claims 13 to 14 of the patent application scope The method wherein the dielectric elastomer layer (4) or the piezoelectric layer (6) is at least partially printed with the conductive layer (12, 14).