DE102019121540A1 - Device for measuring pressure and / or humidity - Google Patents

Abstract

The invention relates to a device for measuring pressure and / or humidity and a method for measuring pressure and / or humidity. The device comprises at least one sensor for measuring pressure and / or humidity, the sensor comprising at least one capacitor with at least two electrodes, which are arranged in relation to one another, in particular in a horizontal direction along and on an, in particular flexible, carrier material. At least one dielectric layer is arranged between the electrodes. The invention is characterized in that at least one electrode and / or the dielectric layer, at least in places, at least one, at least partially liquid-permeable and / or liquid-absorbing moisture layer, is arranged on a side facing away from a carrier material. The at least one electrode and / or the dielectric layer are thus arranged in a transverse direction between the carrier material and the moisture layer. For example, a capacitance changes at least partially due to the liquid at least partially striking the dielectric layer, a processing unit being set up and provided for measuring and / or storing this change, so that a capacitive humidity sensor is created.

Description

The present invention relates to a device for measuring pressure and / or humidity and a method for measuring pressure and / or humidity, comprising the respective preambles of claims 1 and 8.

The device according to the invention for measuring pressure and / or humidity comprises at least two sensors for measuring pressure and / or humidity, at least one of the sensors, but preferably both of the sensors comprising at least one capacitor with at least two electrodes, which, in particular in one horizontal direction, are arranged along and on a, in particular flexible, carrier material to one another, with at least one dielectric layer being arranged between the electrodes.

The horizontal direction is preferably a main direction of extent of the flexible carrier material.

In this context, “flexible” means that the carrier material is at least in places flexible and therefore elastic.

In particular, the carrier material can be a woven fabric or some other clothing material such as a polyester.

The dielectric layer thus separates the two electrodes in a horizontal and / or in a transverse direction perpendicular thereto.

According to the invention, at least one electrode and / or the dielectric layer, at least in places, at least one, at least partially liquid-permeable and / or liquid-absorbing moisture layer is arranged on a side facing away from the carrier material, with the at least one electrode and / or dielectric layer in a transverse direction between the carrier material and the moisture layer are arranged so that a capacitance is at least partially changed by the liquid at least partially hitting the dielectric layer, at least one processing unit being set up and provided for measuring and / or storing this change so that a capacitive moisture sensor is created.

Both sensors are preferably controlled and / or regulated by the processing unit, for example precisely one.

A capacitive humidity sensor is basically a capacitor whose dielectric preferably consists of a hygroscopic polymer layer, which absorbs (absorbs) or releases (desorbed) humidity according to the humidity of the ambient air until a state of equilibrium (diffusion gradient = 0) is reached. The dielectric constant of the polymer material changes as a function of the moisture content.

The task of the processing unit is, among other things, to determine the relative humidity as precisely as possible from a measured ambient temperature and the humidity-dependent capacitance value of the sensor.
According to at least one embodiment, the device for measuring pressure and / or humidity comprises at least two sensors for measuring pressure and / or humidity, at least one of the sensors, but preferably both of the sensors each having at least one capacitor with at least two electrodes, which, in particular are arranged in a horizontal direction along a, in particular flexible, carrier material and on a, in particular flexible, carrier material to one another, with at least one dielectric layer being arranged between the electrodes, and furthermore with at least one electrode and / or the on a side facing away from the carrier material dielectric layer at least in places at least one at least partially liquid-permeable and / or liquid-absorbing moisture layer is arranged, with the at least one electrode and / or the dielectric layer in a transverse direction between the carrier material and the fire chteschicht are arranged so that a capacitance is at least partially changed by the liquid at least partially hitting the dielectric layer, at least one processing unit is set up and provided to measure and / or store this change, so that a capacitive humidity sensor is created, and further whereby both sensors can be controlled and / or regulated by the, for example exactly one, processing unit.
The moisture layer can be formed with a dielectric material. The material of the moisture layer can be different from the material of the water-impermeable layer.

The sensor and / or the processing unit can be supplied with electrical energy by means of a battery or a landline power supply.

Alternatively or in addition, it is possible to generate electrical energy to supply the sensor and / or processing unit by means of so-called “energy harvesting”.

Energy harvesting (literally translated as energy harvesting) is the name given to the production Small amounts of electrical energy from sources such as ambient temperature, vibrations or air currents for mobile devices with low power. The structures used for this are also referred to as nanogenerators. With wireless technologies, energy harvesting avoids restrictions due to wired power supply or batteries.

• • Piezoelektrische Kristalle erzeugen bei Krafteinwirkung, beispielsweise durch Druck oder Vibration, elektrische Spannungen. Diese Kristalle können an oder auf dem Trägermaterial angeordnet sein.
• • Thermoelektrische Generatoren und pyroelektrische Kristalle gewinnen aus Temperaturunterschieden elektrische Energie. Diese Generatoren können an oder auf dem Trägermaterial angeordnet sein.
• • Über Antennen kann die Energie von Radiowellen, eine Form von elektromagnetischer Strahlung, aufgefangen und energetisch verwendet werden. Ein Beispiel dafür sind die passiven RFIDs. Diese Antennen können an oder auf dem Trägermaterial angeordnet sein.

• • Photovoltaik, elektrische Energie aus der Umgebungsbeleuchtung.
• • Osmose.

Energy harvesting options:

• • Piezoelectric crystals generate electrical voltages when a force is applied, for example through pressure or vibration. These crystals can be arranged on or on the carrier material.
• • Thermoelectric generators and pyroelectric crystals generate electrical energy from temperature differences. These generators can be arranged on or on the carrier material.
• • The energy of radio waves, a form of electromagnetic radiation, can be captured and used energetically via antennas. Passive RFIDs are an example of this. These antennas can be arranged on or on the carrier material.

• • Photovoltaics, electrical energy from ambient lighting.
• • osmosis.

According to at least one embodiment, the processing unit is set up and provided to control each of the sensors separately or at the same time, so that individual sensor addressing is thereby implemented to address each of the sensors individually. An IP address can therefore be assigned to each sensor. As an alternative or in addition, the control via the IP address can also be implemented via a logic circuit. For the purposes of the invention, a logic circuit denotes such a circuit which is constructed on the basis of digital and / or analog logic. For example, one or both sensors is activated if an ambient temperature (and / or humidity) is exceeded or undershot and / or a pressure exerted on the sensors and / or the processing unit is undershot or exceeded. A change in pressure over time and its assigned value can also be used as a reference variable. The above values can either be measured by the sensor itself or by other placement sensors. “Controlling” a sensor within the meaning of the invention can mean that the sensors are only subjected to a supply current and / or a supply voltage by the processing unit. Activation can be equated with putting into operation.

It is also conceivable that initially only a part of the sensors, for example only one of the sensors, is activated and thus started up, and only once the ambient temperature, ambient humidity and / or one or more pressure values are exceeded or fallen below put into operation sensors at least one further sensor, for example all sensors, are controlled.

According to at least one embodiment, the processing unit is or comprises an ASIC (application-specific integrated circuit). An application-specific integrated circuit (ASIC, also custom chip) is an electronic circuit that has been implemented as an integrated circuit. ASICs are manufactured worldwide by many manufacturers according to customer requirements and usually only supplied to them. This is how the ASIC differs from other microchips. If a component developed as an ASIC is sold on the market, it is often referred to as an application-specific standard product (ASSP).

According to at least one embodiment, at least one device comprises at least two sensors. In this respect, a sensor group can already be formed by these two sensors. The two sensors can then be controlled and / or regulated by a common processing unit.

It is conceivable that the plurality of processing units forms a processing network, the acquisition, processing and / or forwarding of the sensor data and / or the processing data of each sensor and / or each processing unit being controlled by at least one control device (master). One or more processing units can be identical to the CPU described above.

However, it is also possible that one or more of the processing units represent the master, which controls the other processing units (slaves) and / or the other sensors (slaves).

For example, one of the processing units and / or the CPU, after the device has been put into operation (for example after the device has been switched on), can select such sensors which are put into operation for a predefinable period of use. Alternatively, all or some sensors can also be put into operation, but then it is conceivable that a processing unit and / or the CPU, in particular for the purpose of saving energy, only forwards data of a predetermined number (ie fewer than all sensors) from sensors to the CPU (filtering).

This master processing unit can preferably communicate with the CPU as the only unit.

As an alternative or in addition, it is also conceivable that one or all processing units and / or a sensor (slave or master) communicate directly with the CPU.

According to at least one embodiment, the processing network can be subdivided into at least two, only logically separate, network segments (VLANs) by means of at least one VLAN switch and each of the detection elements depending on the control by a VLAN switch and / or the control device and thus by each of the network segments can be controlled.

If, for example, a very large area (for example a textile) is equipped with a large number of sensors and processing units used here, individual processing units and / or sensors can then be categorized in a particularly simple manner (according to different priorities etc.). In one embodiment, instead of a physical network subdivision, a “virtual”, ie VLAN, subdivision is chosen. This is because this ensures that changes in the categorization of the processing units and / or sensors can be responded to particularly quickly and without complex conversion work.

According to at least one embodiment, the control system comprises at least one processing network, which can be subdivided into at least two, only logically separated, network segments (VLAN) by means of at least one VLAN switch of the processing network, and with each processing unit and / or each of the sensors depending can be controlled from the control by the VLAN switch through each of the network segments.

For this purpose, the VLAN switch can be installed in at least one of the processing units and / or sensors or in a separate component.

According to at least one embodiment, the VLAN switch is used to prioritize the individual network segments, in particular with regard to their data exchange.

According to at least one embodiment, each processing unit and / or each network segment is assigned at least one VLAN ID, with at least one sensor or another processing unit being controllable via each of the VLAN IDs. Individual sensors and / or individual processing units can form their own sub-network.

In order to communicate across network boundaries, static project-dynamic routes are used in the prior art. This model of separation is clear and concise and has been used for years. However, this has the disadvantage that broadcast requests in the subnet are visible to all participants and have to be viewed by the end points. In other words, different end devices could previously only be controlled via separate and physically separate switches that were assigned to each subnet. However, such a structure is particularly expensive and extensive in design.

As already mentioned above, the design of each subnetwork with a separate switch and separate physical data lines is therefore particularly dispensed with, so that a single physical structure can be used for the entire network, this physical structure, i. H. Network architecture, is only separated on the basis of a logical, in particular also a mathematical, distinction (i.e. thought).

The abbreviation “VLAN switch” denotes such a network switch, which is set up and intended to operate a network in the form of a Virtual Local Area Network (VLAN).

In this respect, the network segments now claimed, which can each be designed in the form of a VLAN network, make it possible for the separation of the network to be divided into several logical segments, that is to say the network segments.

In contrast to the physical separation through the assignment to a switch port, the devices are logically separated by a VLAN ID when they are separated by VLANs. The data stream of each station is given an identifier (the VLAN “tag”). This identifier determines whether a data packet belongs to a specific VLAN. All devices with the same VLAN ID are now in a logical network.

In particular, a broadcast can be limited through the logical separation of the individual networks. Broadcasts will be namely distributed only to members of the same VLAN and not to all control elements attached to the switch.

This not only contributes to higher performance, but also to more security, because the data traffic is restricted to fewer addressees. In addition, users or the controls in a VLAN usually have no way of breaking out of the assigned VLAN. Access (or attack) to another computer that does not belong to your own VLAN can therefore be prevented by the network switch. If cross-VLAN communication is necessary, routes can be set up for this purpose.

In particular, it should be noted that the VLAN technology described here can be one which is adapted to the industrial standard IEEE 802.1Q and / or is compatible with it.

The IEEE 802.1Q standard is a prioritization and VLAN technology standardized by the IEEE, which, in contrast to the older, only port-based VLANs, implements packet-based tagged VLANs. The term “tagged” is derived from the English term “material tags”.

Tagged VLANS are therefore networks that use network packets that have a special VLAN tag.

In particular, data fields for V-LAN tagging are defined in the 802.1 Q standard, which can be introduced in the data area of an Ethernet packet.

In this respect, the present network can be designed in the form of an Ethernet communication system.

This has the advantage that existing, older switches can usually also forward such packets. The inserted tag usually consists of several fields, for example four fields with a total length of 32 bits.

2 bytes are used for the protocol ID, 3 bits for the priority field, 1 bit for the canonical format indicator and 12 bits for the VLAN ID.

To uniquely identify a VLAN, each VLAN is therefore initially assigned a unique number. This number is called the VLAN ID. A detection module equipped with VLAN-ID = 1 can communicate with any other device in the same VLAN, but not with a device in another VLAN, such as B. ID = 2, 3, ....

In order to differentiate between the VLANS, an Ethernet frame is extended by 4 bytes according to the IEEE 802.1Q standard. Of these, 12 bits are provided for the VLAN ID, so that (without using the canonical format) 4096-2 = 4094 VLANS are theoretically possible.

It is conceivable that the individual logical network connections according to an OPC standard, i. H. for example in the form of OPC UA connections. In particular, it is conceivable that several OPC UA endpoints with different IP addresses, VLAN IDs and prioritization according to the above-mentioned IEEE 802.1Q standard are available per network segment via the control device.

If a network segment that has been assigned a specific VLAN ID unambiguously, preferably unambiguously, has a higher priority than a network segment that differs therefrom, only in logical terms, with a correspondingly different VLAN ID, the control device and / or the VLAN switch can be provided to initially prefer the data exchange of the higher-priority network segment in order to allow the lower-priority network segment to be processed only after the tasks assigned to this higher-priority network segment have been removed.

In other words, the following generally applies: Assignment and configuration of the OPC UA endpoints to a specific network segment according to the VLAN ID and assignment of a priority according to the priority of the corresponding VLAN.

According to at least one embodiment, each sensor and / or each processing unit is assigned at least one VLAN ID and each network segment is in turn assigned at least one, for example exactly one, unambiguously, preferably one-to-one, VLAN ID, with at least one control element over each of the VLAN IDs is controllable. According to at least one embodiment, at least one device comprises at least one temperature sensor, wherein the temperature sensor measures an ambient temperature and / or a temperature of a sensor and forwards it to the processing unit of a device and / or to the central CPU.

In accordance with at least one embodiment, the central CPU determines a degree of utilization (CPU load and / or memory consumption) of at least one processing unit, with the Processing unit and / or at least the sensor assigned to this processing unit, this (s) is at least partially throttled in its performance or completely switched off

According to at least one embodiment, the processing unit and the at least two sensors are arranged together in a star shape, specifically in such a way that the processing unit forms a star center and the sensors each form star branches. The sensors are preferably connected to the processing unit via their respective star branches on the shortest possible route, preferably via a single straight connection. The star branch can therefore be an electrical connection, in particular a cable connection, which is free from kinks and bends. This star-shaped arrangement not only realizes a particularly simple and inexpensive production, it is also possible for each of the sensors to cover its own sensor segment (= corresponding to a cake segment) and at the same time to have a high detection density, especially via the sensor described here, so that The advantages of the sensor described here not only add up together with the star-shaped arrangement, but even create a synergistic effect together. This is also because the individual sensors can be arranged on a common carrier material, for example the carrier material, and each displacement and / or loading of the star branch leads to a greater extent to a tensile-compressive stress transmitted from the star branch to the sensor. This can be due to the fact that even the smallest compressive and / or tensile stresses are transferred to the sensor along linear force paths through the “shortest path”. In addition, the processing unit can also be arranged on the same carrier material.

According to at least one embodiment, the processing unit and the at least two sensors are arranged together along a strip and / or on a strip-shaped material, in particular the carrier material. At least one sensor with at least one processing unit can then alternate, for example periodically, along the main direction of extent of the strip-shaped carrier material. In the case of several processing units, each of the processing units and / or the CPU (if this is available) can store which processing unit controls which sensor and thus addresses it.

According to at least one embodiment, the sensor is additionally a capacitive pressure sensor, the processing unit also being set up and provided to measure and / or store a change in capacitance of the capacitor caused by external pressure.

In principle, a capacitive sensor is a sensor that works on the basis of the change in the electrical capacitance of an individual capacitor or a capacitor system. The capacity to be measured can be influenced in various ways, which are primarily determined by the intended use.

• - Eine Platte wird durch den zumessenden Effekt verschoben und/oder verformt, wodurch sich der Plattenabstand und damit die elektrische messbare Kapazität ändern.
• - Die Platten sind starr und die Kapazität an Sich ändert sich dadurch, dass ein elektrisch leitendes Material oder ein Dielektrikum in unmittelbare Nähe gebracht wird.
• - Die wirksame Plattenfläche ändert sich, indem die Platten wie bei einem Drehkondensator gegeneinander verschoben werden.

A capacitive sensor is based, among other things, on the fact that two electrodes, one of which can be the surface to be measured, form the "plates" of an electrical capacitor whose capacitance or change in capacitance is measured, which can be influenced as follows:

• - A plate is displaced and / or deformed by the effect being measured, which changes the plate spacing and thus the measurable electrical capacitance.
• - The plates are rigid and the capacitance changes in that an electrically conductive material or a dielectric is brought into close proximity.
• - The effective plate area changes when the plates are shifted against each other like a rotary capacitor.

In order to be able to detect even small changes better, the actual measuring electrode can often be surrounded by a shielding electrode that shields the inhomogeneous edge area of the electric field from the measuring electrode.This results in an approximately parallel electric field with the known characteristics of an ideal between measuring electrodes, usually grounded counterelectrodes Plate capacitor.

A capacitive pressure sensor is in particular one in which the change in capacitance due to the bending of a membrane and the resulting change in the plate spacing is evaluated as a sensor effect. For example, the membrane is the above-mentioned dielectric or else the individual capacitor electrodes, which can in particular be designed in the form of a plate. In other words, in such an embodiment, a capacitive humidity sensor is combined with a capacitive pressure sensor in a novel way, but without these components forming separate elements or two separate sensors, rather the present embodiment is a "two in one" -Concept in which the same sensor functions as both a humidity sensor and a pressure sensor.

According to at least one embodiment, the carrier material is a woven fabric, in particular in which it is electrical Conductor tracks for making electrical contact with the sensor and the processing unit are woven in.

For the purposes of the invention, a woven fabric is therefore a fabric that has been woven manually or by machine on the basis of individual threads.

The electrical conductor tracks can therefore be integrated in a fabric in addition to the usual fibers and strands of fabric, or they can replace individual strands of fabric that form the fabric network.

Depending on the distance and properties of the individual threads (twisted up, fluffy, etc.), very loose fabrics such as bandages or dense fabrics such as brocade fabric can arise. Textiles are used longitudinally elastic through rubber threads used as warp threads (more ribbons used) or crimped and bulked yarns. They are tense, processed and contract when at rest. Bulky yarns consist of textured, i.e. crimped, synthetic fibers. The crimp changes the properties of the synthetic fibers. The yarns spun on it are very elastic and voluminous and have good thermal insulation.

For example, the carrier material can be part of a cover material for a seat, in particular a vehicle seat or an office chair. In this respect, the sensor, but preferably the entire device, can be applied to the cover material of such a seat or integrated into such a seat.

For example, the processing unit is set up and provided to record the individual humidity and pressure values and to determine at least one respective characteristic value from a combination of the individual humidity and pressure values, from which it can be derived which individual (with weight and / or height) ) currently occupies the vehicle seat.

For example, a weight of the respective person can be derived and determined from the pressure measurement by the processing unit. The respective humidity that the respective person emits to the sensor can also be measured, the respective characteristic value being, for example, a product of the relative humidity value times the load weight determined by the processing unit.

If such a characteristic value exceeds a corresponding limit value, the processing unit can issue a warning, in particular by means of a connection to the electronics of the vehicle. This warning could be that the seat is overcrowded or the driver is sweating too much. This warning can, however, also be replaced by a corresponding display indicating which occupancy type is using the seat. An occupancy type can be a weight classification of a particular user, or it can also be a question of whether the user is an animal, a person or a thing. The processing unit can therefore preferably be integrated into display electronics of the vehicle, but at least can be connected to such.

For this purpose, it is conceivable that the processing unit connects to a receiving unit of the vehicle, for example by means of Bluetooth or another wireless connection, and the respective characteristic or limit value and / or the respective warning and / or the respective identification of the user is reproduced on a display of the vehicle become.

Alternatively or additionally, it is conceivable that these individual values and / or identifications can also be called up and / or displayed externally. For example, the car can be monitored for overcrowding by an external controller.

For example, the processing unit can be connected to a triggering unit of an airbag by means of a data connection, so that the processing unit can also control and / or regulate the triggering unit, in particular with regard to a triggering time of the airbag. Additionally and / or alternatively, it is possible for the processing unit to supply a controller unit of the airbag with data, for example with regard to an occupancy type, position and / or weight of a user of the vehicle seat.

These data can lead to the deployment time and the deployment sequence of the airbag being adapted to the user, so that personal injury to the user is avoided.

According to at least one embodiment, at least one electrode and / or dielectric layer is printed on the carrier material or on a, in particular water-impermeable, layer arranged on the carrier material or applied by means of a thin-film method.

This means that at least one element, preferably both the electrode and the dielectric layer, is printed by means of a printing process on the carrier material or a preferably electrically non-conductive, further preferably water-impermeable layer applied between the sensor and the carrier material.

The printing process can be an inkjet process, for example.

For example, the processing unit is applied to the carrier material in the same way as the sensor. For this purpose, it is conceivable that the processing unit, but at least one, in particular conductive, layer of the processing unit is, for example, printed onto the carrier material. The data communication between the processing unit and the sensor can then take place via the conductor tracks mentioned above. These conductor tracks can be at least partially, but preferably completely, woven into the woven fabric or even form individual fibers of the woven fabric itself.

For example, at least one electrode is designed to be flat. This means that a thickness of the electrode is negligible compared to its surface area. Such an electrode can therefore be produced in particular by means of a printing process.

Alternatively, a thickness of at least one electrode can be at most 5 mm. To this end, the printing method can be used several times, so that at least two, but then preferably more, individual printing layers are stacked on top of one another.

Furthermore, the electrode can also be arranged on the carrier material by means of a 3D printing process.

The FDM process (Fused Deposition Modeling)

Alternative names: Fused Filament Fabrication (FFF), Fused Layer Modeling (FLM)

The process refers to the application of layers (extrusion) of a material through a hot nozzle. The consumables are in the form of a long wire (so-called filament) on a roll and are pushed into a print head by the conveyor unit, where they are melted and placed on a print bed. The print head and / or print bed can be moved in three directions. In this way, layers of plastic can be applied to one another in stages.

The SLS process (selective laser sintering)

In contrast to the sintering process, in which substances are bonded together in powder form under the action of heat, in the SLS process this is done selectively by means of a laser (alternatively electron beam or infrared beam). So only a certain part of the powder is fused together.

For this purpose, a thin layer of powder is always applied to the printing bed by the coating unit. The laser (or other energy source) is now aimed precisely at individual points of the powder layer in order to form the first layer of the print data. The powder is melted or melted and then solidifies again by cooling it slightly. The unmelted powder remains around the sintered areas and serves as a support material. After a layer has solidified, the print bed lowers by a fraction of a millimeter. The coating unit now moves over the print bed and applies the next layer of powder. Then the second layer of the print data is sintered by the laser (or other energy source). This creates a three-dimensional object in layers.

Three-Dimensional Printing (3DP)

The 3DP process works very similarly to selective laser sintering, but instead of a directed energy source, a print head moves over the powder. This releases tiny droplets of binding agent onto the underlying powder layers, which are thus bonded together. Otherwise this procedure is the same as the SLS procedure.

Stereolithography (SLA)

Instead of a plastic wire or printing material in powder form, liquid resins, so-called photopolymers, are used in the stereolithography process. They are hardened in layers by UV radiation and thus create three-dimensional objects. To do this, the construction platform in the Harz Basin is gradually lowered. There are also variants (the so-called Polyjet process) without a whole basin with liquid resin. For this, an epoxy resin is applied drop by drop from a nozzle and immediately cured by a UV laser.

Laminated Object Manufacturing (LOM)

Alternative designation: Layer Laminated Manufacturing (LLM)

The process is based neither on chemical reactions nor on a thermal process. The contour is cut with a separating tool (e.g. a knife or carbon dioxide laser), a film or a plate (e.g. paper) and glued on top of each other in layers. By lowering the construction platform, a layered object is created from glued, overlapping foils.

One or more water-impermeable layers and / or also the moisture layer can can be applied in the same type and / or thickness as the electrode.

According to at least one embodiment, the moisture layer completely covers the capacitor.

This can mean that the moisture layer delimits and closes off the sensor towards the outside, that is to say in the transverse direction, so that the sensor is arranged between the moisture layer and the carrier material.

According to at least one embodiment, the sensor has at least one further capacitor, which is arranged in the transverse direction below or above the capacitor and spaced apart from the capacitor by a further water-impermeable layer or is arranged below this further water-impermeable layer, so that a capacitor stack is created.

The further capacitor can be constructed in the same way as the capacitor and can also be arranged on the further water-impermeable layer in the same way as the capacitor.

By means of such a capacitor stack, the sensor system can be particularly easily refined insofar as it is conceivable that, with two sensors forming the capacitor stack, both sensors perform the same tasks, but the individual sensors determine respective measured values which, taken together, conclude a mean value to let. For example, the (relative) humidity of the environment is measured by each of the two sensors, the average humidity value being determined from these two measured values. The same can happen accordingly with the pressure measurement, so that the accuracy of the entire measurement, in particular a combination of the measurements of (relative) humidity and the respective pressure, can be configured particularly precisely.

According to at least one embodiment, the water-impermeable layer and / or the further water-impermeable layer at least partially form the dielectric view itself.

This can mean that, instead of separately positioning a dielectric layer next to the water-impermeable layer and / or next to the further water-impermeable layer, this dielectric layer itself is formed by the water-impermeable layer and / or the further water-impermeable layer.

Such a production of the dielectric layer by the water-impermeable layer (s) therefore forms a particularly simple and cost-effective production method for an inexpensive device.

Apart from this, the electrodes, the dielectric layer and the water-impermeable layer (s) can in principle be arranged in relation to one another in such a way that an electrical short circuit is prevented in any case.

According to at least one embodiment, a maximum thickness of the moisture layer is at least 30% and at most 80% of the maximum thickness of the water-impermeable layer and / or the maximum thickness of the further water-impermeable layer.

This not only ensures a particularly flat sensor, but also ensures a particularly fast response time to changes in humidity. The moisture acting on the moisture layer from the outside therefore does not have to travel long distances to the dielectric.

Furthermore, the present invention relates to a method for measuring pressure and / or humidity, it being particularly noted that all of the features disclosed for the device described above are also disclosed for the method described here and vice versa.

According to at least one embodiment, the method for measuring pressure and / or moisture initially comprises a first step by means of which at least one sensor for measuring pressure and / or moisture is provided, the sensor having at least one capacitor with at least two electrodes which, in particular in in a horizontal direction along and on a, in particular flexible, carrier material to one another, with at least one dielectric layer being arranged between the electrodes.

According to the invention, at least one electrode and / or the dielectric layer, at least in places, at least one, at least partially liquid-permeable and / or liquid-absorbing moisture layer is arranged on a side facing away from the carrier material, with the at least one electrode and / or the dielectric layer in a transverse direction between the carrier material and the moisture layer are arranged so that a capacitance changes at least partially as a result of the liquid at least partially striking the dielectric layer, a processing unit measuring and / or measuring this change stores, so that a capacitive humidity sensor is created.

The method described above has the same advantages and advantageous configurations as the device described above.

The invention described here is described in more detail below using two exemplary embodiments and the associated figures.

Components that are the same or have the same effect are provided with the same reference symbols.

In the 1 a device according to the invention for measuring pressure and / or humidity is shown in a first embodiment.

In the 2 a schematic perspective view is shown an exploded view shown in relation to the layer order.

In the 3 a further embodiment of a device described here is shown.

The 4th and 5 each show further configurations of the device described here.

6th shows a combination of 4th and 5 .

How now that 1 can be seen, there is a device 100 shown for measuring pressure and / or humidity.

An example is a sensor there 1 shown, the sensor 1 shows a capacitor stack with a capacitor 20th , as well as a capacitor 30th , with the individual electrodes 10 , 11 the capacitors 20th , 30th in the horizontal direction H1 are arranged one above the other, but of course alternatively an arrangement of the individual electrodes 10 , 11 a single capacitor 20th , 30th in the transverse direction Q1 which is perpendicular to the horizontal direction H1 runs and thus also perpendicular to the main direction of extent of the sensor shown there 1 can run or be arranged.

The individual electrodes 10 , 11 are on a carrier material 13 arranged. With the carrier material 13 it can in particular be a woven fabric, in particular a flexible woven fabric.

On the carrier material 13 is a waterproof layer 4th arranged, on this waterproof layer 4th the two electrodes 10 , 11 of the capacitor 20th in the horizontal direction H1 are printed.

The electrodes 10 , 11 of the capacitor 20th are completely covered by another impermeable layer 14th surround. On this waterproof layer 14th is the further capacitor in the same way 30th with appropriate electrodes 10 , 11 imprinted. In addition, in the present exemplary embodiment there are exposed outer surfaces of the individual electrodes 10 , 11 of the further capacitor 30th preferably completely of a water-permeable and / or water-absorbing moisture layer 3 surround.

About this layer of moisture 3 can water on a dielectric layer 4th meet, which present in the horizontal direction H1 between the respective electrodes 10 , 11 a capacitor 20th , 30th is arranged.

In the present embodiment of the 1 and 2 forms the waterproof layer 4th itself a dielectric layer 4th of the capacitor 20th on. The same applies to the further impermeable layer 14th in relation to the further capacitor 30th .

By impinging and penetrating the moisture over the moisture layer 3 the dielectric properties in particular of the dielectric layer 2 of the further capacitor 30th changed.

In addition, there is a processing unit 5 recognizable which in the data-technical contract with the two capacitors 20th , 30th stands, this processing unit 5 set up and provided for this purpose, a change in the relative humidity of the environment and / or the moisture layer 3 to eat.

Through the in the 1 The “stackwise” arrangement shown and the fact that the further waterproof layer 14th prevents the capacitor 20th comes into contact with moisture, it can therefore be provided that only the further capacitor 30th and its dielectric layer 4th exposed to moisture. The processing unit 5 then a change in the capacitance of the further capacitor 30th compare with the stable capacitor capacitance of the capacitor 10 so that a particularly simple comparison can be made in the change in the relative humidity and / also in the respective loading pressure.

Through the in the 1 The arrow shown is also a pressure direction under which the sensor 1 is pressurized, shown. Both can preferably by the sensor 1 and in particular by the device 100 measured, evaluated and saved. The processing unit shown as essential in the invention is used for this purpose 5 , which also include corresponding pressure values and the associated changes in the capacity of the individual sensors 1 can measure and evaluate, so that the processing unit 5 a change in capacitance of the capacitor caused by external pressure is also set up and provided for this 20th and in particular also of the further capacitor 30th to measure and / or store.

The moisture layer 3 can be flexible or inflexible. It is also possible that the moisture layer 3 is designed as a woven fabric. In particular, it can be a woven fabric, which was mentioned as an example in the introductory part of the present application. In addition, however, it is also possible that it is the moisture layer 3 is a substrate which, for example, in the form of an epitaxy or an adhesive process on the further capacitor 30th applied, for example glued on.

The waterproof layer 14th and / or the waterproof layer 15th can be just as flexible and inflexible, in particular also in the form of a woven fabric or a substrate in the same way as the moisture layer 3 be trained.

In addition, it is advantageously conceivable that the electrodes 10 , 11 of the two capacitors 20th , 30th on the waterproof layer 14th and the further waterproof layer 15th in the form of a printing process, for example an inkjet printing process.

In the 2 an exploded view is shown, in particular from the 2 the respective arrangement of the electrodes 10 , 11 the capacitors 20th , 30th emerges. The force acting on the sensor shown by the direction of the arrow can again be seen 1 , as well as moisture acting through the individual drops shown schematically. In particular, it can again be seen that the moisture in particular between the electrodes 10 , 11 penetrates and onto the respective water-permeable layer 14th has a significant effect on the electrical property, for example, so that the capacitance of at least the other capacitor 30th like in the 1 explains each changes.

In the 3 is shown in a further embodiment of the invention described here that the sensor 1 from two electrodes 10 and an electrode 11 can exist. The electrodes 10 have one polarity (preferably the same polarity) while the electrode 11 has a polarity different therefrom, but in the right part of the figure 3 the exploded view of the left part of the 3 is shown and it can be seen that three water-impermeable layers 4th , 14th , 15th be used. The electrodes 10 can also have different polarities and / or electrical potentials. The electrodes 10 be electrically connected to each other.

For example, the electrodes 10 , 11 also each have and / or generate a separate polarity and / or a separate electrical potential. The same can also apply to those in the following figures with regard to the electrodes.

For example, the lowermost water-impermeable layer is in turn the water-impermeable layer 14th , the subsequent waterproof layer 15th and those in the transverse direction Q1 a water-impermeable layer 16 arranged thereon is a further water-impermeable layer, one electrode being applied, in particular printed, to a separate water-impermeable layer.

In this stacking of the individual waterproof layers 14th , 15th and 16 is therefore by merging these layers that in the left part of FIG 3 shown capacitor 20th generated, doing this in the transverse direction Q1 who have favourited electrodes 10 each, as can be seen in the corresponding partial image, are arranged on different levels.

Alternatively, the electrode 11 together with at least one of the electrodes 10 in a common plane, that is to say on or in a common water-impermeable layer 4th , 14th , 15th applied so that, for example, only the second of the electrodes 10 on a separate waterproof layer 4th , 14th , 15th needs to be stacked.

In principle, therefore, the individual electrodes 10 , 11 be arranged in different planes in the Q1 direction to each other. For example, there is a paired assignment between exactly one water-impermeable layer 4th , 14th , 15th with exactly one electrode 10 , 11 .

In the 4th is the processing unit 5 and the at least two sensors 1 arranged together in a star shape, in such a way that the processing unit 5 a star center and the sensors 1 each form star branches. There are the sensors 1 via their respective star branch on the shortest possible route, preferably via a single straight electrical connection with the processing unit 5 connected. The star branch can therefore be an electrical connection, in particular a cable connection, which is free from kinks and bends. This star-shaped arrangement not only enables particularly simple and inexpensive production, it is also possible for each of the sensors to cover its own sensor segment (= corresponding to a cake segment) and, at the same time, to have a high detection density, especially via the sensor described here, so that The advantages of the sensor described here together with the star-shaped arrangement not only add up but even create a synergistic effect together. This is also because the individual sensors 1 on a common carrier material 13 can be arranged, and each displacement and / or loading of the star branch leads to a greater extent also to a tensile-compressive stress transmitted from the star branch to the sensor. This can be due to the fact that even the smallest compressive and / or tensile stresses are transferred to the sensor along linear force paths through the "shortest path". Furthermore, the processing unit can also be arranged on the same carrier material.

In the 5 the processing unit 5 and the at least two sensors are arranged together along a strip 40 and / or on a strip-shaped material, in particular the carrier material.
In the 6th are the versions of the 5 and the 6th combined with one another, that is to say that of individual processing units arranged on the strip 40 5 a star branch to at least one other sensor 1 arises. These sensors are then arranged around the strip 40 in a ritual shape 1 can be arranged on another carrier material, for example a carrier material of greater or lesser hardness and / or rigidity.

The invention is not restricted by the description based on the exemplary embodiment. Rather, the invention encompasses every new feature, as well as every combination of features, which in particular includes every combination of features in the patent claims, even if this feature or this combination itself is not explicitly specified in the patent claims or in the exemplary embodiments.

List of reference symbols

1

sensor

3

Moisture layer

4th

dielectric layer / waterproof layer

5

Processing unit

10

electrode

11

electrode

12

electrode

13

Carrier material

14th

waterproof layer

15th

waterproof layer

20th

capacitor

30th

capacitor

100

contraption

200

Procedure

H1

horizontal direction

Q1

Transverse direction

Claims (10)

Device (100) for measuring pressure and / or humidity comprising at least two sensors (1) for measuring pressure and / or humidity, at least one of the sensors, but preferably both of the sensors, (1) each - at least one capacitor (20 ) with at least two electrodes (10, 11) which, in particular in a horizontal direction (H1), are arranged along and on a, in particular flexible, carrier material (13) to one another, with at least one dielectric between the electrodes (10, 11) Layer (4) is arranged, characterized in that on a side facing away from the carrier material (13) at least one electrode (10, 11) and / or the dielectric layer (4) at least in places at least one at least partially liquid-permeable and / or liquid-absorbing moisture layer ( 3) is arranged, with the at least one electrode (10, 11) and / or the dielectric layer (4) in a transverse direction (Q1) between the Carrier material (13) and the moisture layer (3) are arranged so that a capacitance is at least partially changed by the liquid at least partially striking the dielectric layer (4), at least one processing unit (5) being set up and provided for this change measure and / or store so that a capacitive humidity sensor is created, and further where - both sensors (1) can be controlled and / or regulated by the, for example exactly one, processing unit (5). Device (100) after Claim 1 , characterized in that the processing unit (5) is set up and provided to control each of the sensors (1) separately or simultaneously, so that an individual sensor addressing is realized in this way to address each of the sensors (1) individually. Device (100) after Claim 2 , characterized in that the processing unit (5) is or comprises an ASIC (application-specific integrated circuit). Device (100) according to at least one of the preceding claims, characterized in that the processing unit (5) together with the sensors (1) form the control network (4), with the acquisition, processing and / or forwarding of the sensor data from each sensor (slave ) is controlled by the processing unit (5) (master). Method (100) according to Claim 2 or 3 , characterized in that the control network (4) can be subdivided into at least two, only logically separated, network segments (60, 61) (VLAN) by means of at least one VLAN switch (5), and each of the detection modules (2) as a function can be controlled by the control by the VLAN switch (5) and / or the processing unit by each of the network segments (60, 61). Method (100) according to at least one of Claims 4 to 5 , characterized in that the VLAN switch (5) is used to prioritize the individual network segments (60, 61), in particular with regard to their data exchange. The method (100) according to the preceding claim, characterized in that each sensor (1) and / or each network segment (60, 61) is assigned at least one VLAN ID, at least one sensor (1) being controllable via each of the VLAN IDs is. Device (100) according to at least one of the preceding claims, characterized in that the processing unit (5) and the at least two sensors (1) are arranged together in a star shape, specifically in such a way that the processing unit (5) has a star center and the sensors (1 ) each form star branches. Device (100) according to at least one of the preceding claims, characterized in that the processing unit (5) and the at least two sensors (1) are arranged together along a strip and / or on a strip-shaped material, in particular the carrier material. A method (200) for measuring pressure and / or moisture comprising initially a first step by means of which - at least two sensors (1) for measuring pressure and / or moisture are provided, the sensors (1) each - at least one capacitor (20 ) with at least two electrodes (10, 11) which, in particular in a horizontal direction (H1), are arranged along and on a, in particular flexible, carrier material (13) to one another, with at least one dielectric between the electrodes (10, 11) Layer (4) is arranged, characterized in that on a side facing away from the carrier material (13) at least one electrode (10, 11) and / or the dielectric layer (4) at least in places, at least one, at least partially liquid-permeable and / or liquid-absorbent Moisture layer (3) is arranged, with the at least one electrode (10, 11) and / or the dielectric layer (4) in a transverse direction (Q1) z between the carrier material (2) and the moisture layer (3) are arranged so that a capacitance changes at least partially due to the liquid at least partially hitting the dielectric layer (4), a processing unit (4) measuring and / or storing this change, so that a capacitive humidity sensor is created, and further - both sensors (1) being controlled and regulated by, for example, exactly one processing unit (5).

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