Sensor for distance or position measurement

Abstract

The invention relates to a sensor (1) for distance or position measurement, in particular a capacitive or inductive or eddy current effect-based sensor (1), comprising a carrier (3) and a sensor element (2) arranged on or integrated into the carrier (3), in order to achieve reliable measurement performance under a very wide variety of environmental conditions using structurally simple means, the sensor is designed and further improved in such a way that the carrier (3) has a hydrocarbon ceramic laminate, is designed on the basis of a hydrocarbon ceramic laminate, or consists of a hydrocarbon ceramic laminate.

Description

Technical Field

[0001] The present invention relates to a sensor for distance measurement or position measurement, in particular a capacitive or inductive or eddy current effect-based sensor, which has a carrier and a sensor element arranged on or integrated into the carrier. Background Art

[0002] For example, in the field of capacitive sensors, for a long time, sensor elements have been implemented in the form of a sensor surface on a carrier in the form of a circuit board. These carriers or circuit boards are usually composed of a composite material, which consists of a synthetic resin matrix and a reinforcing material. A particularly cost-effective circuit board (FR2) is composed of a material combination of phenolic resin and paper, while the most common circuit board type (FR4) is composed of epoxy resin and glass fiber fabric. The advantage of this insulating material is that compared with sensors composed of metal and insulating / encapsulating layers or sensors based on sintered ceramic carriers, the sensor can be brought to the market at a lower cost and faster speed.

[0003] When a circuit board is used as the carrier or substrate material of a capacitive sensor, it is extremely important that even when the temperature changes, the measurement surface of the sensor (usually composed of copper - carried by the carrier material) should be kept as stable as possible or at least its change should be as calculable and predictable as possible, because the size of the measurement surface plays a decisive role in capacitive distance measurement. A low-cost and flexibly designable capacitive sensor surface is often applied in industrial environments, where, depending on the application, the temperature in the device sometimes far exceeds 100°C.

[0004] It is also important for inductive or eddy current effect-based sensors that even when the temperature changes, the geometry of the sensor coil (usually composed of copper windings - carried by the carrier material) should be kept as stable as possible, or at least its change should be as calculable and predictable as possible, because the geometry of the coil plays a decisive role in inductive / eddy current distance measurement.

[0005] Due to the layer structure of the circuit board, the circuit board is anisotropic with respect to the coefficient of thermal expansion Tk. This coefficient of thermal expansion is typically significantly lower in two directions in the plane (i.e., the x-direction and the y-direction) than in the direction perpendicular to the plane (the z-direction). For example, for FR4, the coefficient of thermal expansion in the plane is approximately 12…14 ppm / °C, while the coefficient of thermal expansion in the perpendicular direction is approximately 70 ppm / °C. Generally, depending on the manufacturer and the differences in other additives, the glass transition temperature Tg of FR4 is between 115 °C and 140 °C. At this temperature, the mechanical and electrical properties of the insulating layer change significantly, and the coefficient of thermal expansion Tk of the circuit board in the direction perpendicular to the plane (i.e., the measurement direction) sometimes "jumps" from the usual 70 ppm / °C to approximately 300 ppm / °C. In addition to the increasingly poor measurement quality, there is also a risk here that the vias of the circuit board will be subjected to great forces and break, which will lead to sensor failures.

[0006] The maximum operating temperature recommended for these FR4-based circuit boards in many applications is insufficient because most circuit board manufacturers give this temperature approximately 25 °C lower than the glass transition temperature Tg. The glass transition temperature Tg of most FR4 circuit boards is 135 °C, and that of special FR5 circuit boards is 150 °C (high-Tg circuit boards), but this does not allow continuous operation at a temperature of 150 °C. In addition, traditional FR4 circuit board sensors often exhibit unpredictable conditions in distance measurements when the temperature rises due to the too large differences in the coefficients of thermal expansion of the various components (the measurement element based on the circuit board - already consists of at least two different main materials: copper and carrier material; may also be pasted in the sensor housing - usually made of stainless steel). This is due to the bending of the capacitive sensor (circuit board), which is caused by the mechanical stress generated by the different expansions of the various components in the plane perpendicular to the measurement direction. For sensors based on coils (inductive or eddy current sensors), the geometry of the coil may change (e.g., a change in diameter), which may lead to a change in inductance and thus to a distortion of the measured value.

[0007] As an alternative to circuit boards made of FR materials, carriers made of ceramics are used in applications with high temperature requirements. This can be a single-layer ceramic substrate, which is provided with printed conductors by means of thick-film printing technology in a so-called hybrid technology. Another possibility is a multi-layer ceramic substrate, which consists of so-called green tapes, which are likewise printed and combined into a rigid circuit board by means of a sintering process. Depending on the temperature range, these are referred to as low-temperature cofired ceramics (LTCC) or high-temperature cofired ceramics (HTCC). However, what all these ceramic technologies have in common is that the resulting circuit board forms a rigid and very brittle substrate that can hardly or only to a small extent withstand mechanical stress. Due to the different manufacturing steps (printing, sintering, separation by laser or water jet cutting, etc.), their manufacturing process is also very time-consuming and expensive, so these technologies are only used in cases where high temperature requirements are present.

[0008] The task that always exists in this field of sensors is to be able to develop a sensor or a component of a sensor that can be flexibly designed, which can be designed and manufactured in a short time, and which can provide as stable and as environmentally insensitive measurement characteristics as possible under the sometimes quite demanding requirements posed by the measurement environment - mainly in the industrial field. Summary of the Invention

[0009] Therefore, the object of the present invention is to provide a sensor of the type described at the beginning, which achieves reliable measurement characteristics in a structurally simple manner under various different environmental conditions.

[0010] According to the present invention, the aforementioned object is achieved by a sensor having the features of claim 1. The sensor is designed and improved such that the carrier has a hydrocarbon ceramic laminate, is designed based on the hydrocarbon ceramic laminate, or consists of the hydrocarbon ceramic laminate.

[0011] It is first recognized according to the present invention that the commonly used carrier materials of known sensors limit the application of known sensors under various different environmental conditions. Furthermore, it is recognized according to the present invention that the aforementioned object can be achieved in an unexpectedly simple manner by using a hydrocarbon ceramic laminate in the carrier region. Specifically, the carrier has a hydrocarbon ceramic laminate, the carrier is designed based on the hydrocarbon ceramic laminate, or the carrier is composed of the hydrocarbon ceramic laminate. Different design solutions according to the present invention can be achieved herein. In one variant, for example, the carrier is completely composed of a hydrocarbon ceramic laminate. A carrier based on one or more hydrocarbon ceramic laminates can provide an almost direct alternative to traditional carriers in the field of flexibly designable and cost-effective capacitive or inductive / eddy current sensors, especially in the field of capacitive or inductive / sensors operating based on the eddy current effect with a circuit board carrier. A hydrocarbon ceramic laminate is a composite material, and the composite material can have a matrix composed of a hydrocarbon resin and a reinforcing material composed of a glass fiber fabric, wherein the hydrocarbon resin can be filled with mineral fillers (in powder form). This is usually a ceramic filler, but other mineral fillers, such as quartz, can also be considered. Particularly advantageous properties similar to the ceramic materials described at the beginning are achieved by means of a high filling degree. Therefore, the hydrocarbon ceramic laminate achieves very stable mechanical and electrical properties even under strongly fluctuating environmental conditions, such as at up to approximately 280 °C. Thereby, the coefficient of thermal expansion is very uniform and has no or only very small anisotropy. In addition, the coefficient of thermal expansion is in the range of 10…12 ppm / °C, which is close to the Tk of copper.

[0012] Therefore, the sensor according to the present invention provides a sensor that achieves reliable measurement characteristics under various different environmental conditions in a structurally simple manner.

[0013] In terms of a particularly simple and reliable structure, the carrier can be designed as a circuit board or have a circuit board. Using a circuit board as a carrier has proven to be effective in practice and enables the flexible and cost-effective manufacture of sensors.

[0014] In terms of the particularly reliable and simple manufacture of the sensor, the sensor element can be designed as a sensor element introduced or applied or etched onto or into the carrier or onto or into the metal layer of the carrier, or designed as a sensor surface introduced or applied or etched onto or into the carrier or onto or into the metal layer of the carrier. If the sensor element has one or more coils, the coils can be introduced or applied or etched in the form of printed conductors or windings.

[0015] In a capacitive sensor, the sensor element can be composed of planar electrodes, which form the measuring electrode, the shielding electrode, and, if necessary, the ground plane. In an inductive or eddy current sensor, the sensor element can be composed of one or more coils, which form the inductance.

[0016] The sensor element can be structured in a conductive layer on or within a carrier in a suitable manner and thus the desired surface or coil can be fabricated. The method here can be (selective) etching or laser ablation of a copper surface, or the application of a metal surface or metal conductor by coating (sputtering, thick film, thin film) or lithography methods. Combinations of multiple methods can also be considered, in such a way that, for example, a coil or surface fabricated by coating is post-processed by laser machining. Generally in printed circuit board technology, metal surfaces or metal printed conductors are made of copper. However, other metals are also particularly suitable for coating methods. This enables the dimensions of the sensor element to be flexibly designed according to the corresponding application scenarios.

[0017] In a specific embodiment, the sensor can have a layer structure composed of a hydrocarbon ceramic laminate and at least one surface made of copper or metal and / or at least one copper wire or metal wire. More specifically, the surface and / or the copper wire or metal wire can be applied or introduced onto or into the hydrocarbon ceramic laminate. With this layer structure, various different design possibilities are achieved, so that the sensor design can be reliably adapted to the corresponding application scenarios.

[0018] In order to reliably and simply implement a capacitively operated sensor, at least one surface made of copper or metal can specifically form the electrode surface or sensor surface for capacitive measurement.

[0019] In order to reliably and simply implement an inductive or eddy current effect-based sensor, at least one coil made of copper or metal can specifically form the inductance for inductive or eddy current effect-based measurement.

[0020] As required, the sensor can be arranged in a housing, which has or is coupled to the housing. In this regard, the design can also be flexibly adapted to the corresponding application requirements of the sensor and the implementation with a housing ensures a particularly protected design and thus particularly reliable measurement characteristics.

[0021] In a specific embodiment, the housing can be made of metal. Due to the stability of the metal, particularly high protection for the sensor elements arranged in the housing can be ensured. Instead of or in addition to this, the housing can have at least one assembly through-hole and / or at least one assembly element. Through such an assembly through-hole and / or assembly element, the reliable positioning of the sensor at the use position can be achieved by means of the housing. The reliable positioning enables reliable measurement by means of the sensor.

[0022] In a further particularly simple and reliable structural manner, the connection area of the sensor or the sensor can have an injection-molded coating structure or a housing manufactured by injection molding technology. Such an injection-molded coating structure or a housing manufactured by injection molding technology can replace the housing and / or can be realized by means of plastic in a reliable manner.

[0023] In terms of particularly reliable control and / or transmission of the measurement data to the evaluation electronic device, the sensor element can be in contact connection with the evaluation electronic device through a coaxial or triaxial wire. A particularly high shielding effect can be achieved by means of the triaxial wire.

[0024] In the particularly simple realization of, for example, a gap sensor, the carrier can have at least two sensor elements that measure in different directions. Here, the two directions can point in opposite directions, whereby the gap width can be particularly easily measured.

[0025] In one embodiment, in terms of a particularly stable design of the sensor and thus in terms of particularly reliable measurement characteristics, the sensor or the carrier can have a multi-layer hydrocarbon ceramic laminate.

[0026] Furthermore, in terms of a particularly stable design of the sensor, one or more layers of fiberglass fabric can be embedded in the hydrocarbon ceramic laminate. Here, one or more layers of fiberglass fabric can be assigned to each layer of the hydrocarbon ceramic laminate. Specifically, multiple layers of fiberglass fabric can be embedded or arranged in one layer of the hydrocarbon ceramic laminate.

[0027] In one embodiment, the hydrocarbon ceramic laminate can have at least one filler, preferably ceramic powder, and more preferably ceramic powder with a high filling degree. Thereby, a particularly stable sensor structure can also be achieved.

[0028] In terms of a particularly high shielding effect and thus reliable measurement, the sensor element can have a shielding electrode in one layer of the hydrocarbon ceramic laminate, and the sensor or the carrier has an additional shielding electrode in another layer of the hydrocarbon ceramic laminate. Thereby, a particularly efficient quasi-two-stage shielding can be achieved.

[0029] According to an embodiment of the sensor according to the invention, a capacitive sensor or an inductive or eddy current effect-based sensor can be realized to perform distance measurement and / or position measurement by means of a sensor element, which is integrated into a flat substrate serving as a carrier or applied to the flat substrate, wherein the substrate is made of a hydrocarbon ceramic laminate or may have a hydrocarbon ceramic laminate. Description of the Drawings

[0030] There are now various possibilities to advantageously design and further improve the technical solution of the present invention. For this purpose, on the one hand, reference can be made to the dependent claims, and on the other hand, reference can be made to the following description of the preferred embodiments of the sensor according to the invention. In combination with the description of the preferred embodiments with the aid of the drawings, the preferred configurations and improvement solutions of the technical solution of the present invention will generally also be described. Shown in the drawings:

[0031] Figure 1 A first embodiment of the sensor according to the invention is shown in a partially cut-away side view,

[0032] Figure 2 A second embodiment of the sensor according to the invention is shown in a partially cut-away side view and in a top view,

[0033] Figure 3 A third embodiment of the sensor according to the invention is shown in a partially cut-away side view and in a top view,

[0034] Figure 4 A third embodiment of the sensor according to the invention from Figure 3 is shown in a perspective view,

[0035] Figure 5 A fourth embodiment of the sensor according to the invention is shown in a partially cut-away side view, in another partially cut-away side view, and in a top view,

[0036] Figure 6 A fifth embodiment of the sensor according to the invention is shown in a partially cut-away side view and in a top view,

[0037] Figure 7 A sixth embodiment of the sensor according to the invention is shown in a perspective view,

[0038] Figure 8 A hydrocarbon ceramic laminate is shown in a cross-sectional view, and

[0039] Figure 9 A sensor according to the invention having a single-layer or multi-layer structure is shown in a cross-sectional view.

[0040] In the following-described embodiments of the sensor 1 according to the invention, the same reference numerals refer to the same elements. Detailed implementation manners

[0041] In Figure 1 FIG. 6 shows a first embodiment of a sensor 1 according to the present invention, the sensor having a specific inductive measuring element / sensor element 2, the measuring element / sensor element together with a circuit board 3 serving as a carrier 3 forming a material composite structure having a hydrocarbon ceramic laminate and a copper surface and / or copper traces. The material composite structure has excellent thermal stability over the entire temperature application range. The sensor element 2 is located in a metal housing 4. The contact connection is made through a coaxial or triaxial wire 5.

[0042] Hereinafter, an embodiment with a triaxial wire 5 is described herein. The advantage of the triaxial wire is that it achieves a better shielding effect compared to the coaxial connection mode of the sensor 1. The middle conductor 6 of the wire 5 is in contact connection with the measuring electrode 7 on the sensor element 2. The internal shield wire 8 is electrically connected to a metal shield cap 9, which is arranged on the back side of the sensor element 2. The metal shield cap 9 is conductively connected to a shield electrode 10 on the front side / measuring side of the sensor element 2. Through this arrangement, active shielding (also known as shielding technology) of the measuring electrode 7 can be achieved. The external shield layer 11 of the wire 5 is conductively connected to the housing 4. For this purpose, a support sleeve 12 made of metal is sleeved onto the wire 5. The support sleeve 12 has two functions: firstly, the support sleeve makes the external shield layer 11 in electrical contact connection with the housing 4, and secondly, the support sleeve supports the wire 5 onto a crimping portion 13, and the wire 5 is mechanically connected to the housing 4 by means of the crimping portion.

[0043] Figure 2 A second embodiment of the sensor 1 according to the present invention is shown in side view A and top view B. The sensor 1 has a triaxial plug 14 for connection to an evaluation electronic device (not shown here). The housing 4 has two mounting holes 15a, 15b for fixing or positioning the sensor 1 at a suitable location. The housing 4 can be fixed and / or positioned on a suitable element, for example, by means of bolts (not shown here) passing through the mounting holes 15a, 15b.

[0044] In Figure 3 FIGS. 7 and 8 show a third embodiment of a sensor in the form of a capacitive gap sensor 16 according to the present invention in side view A and top view B. As in the first embodiment shown in Figure 1 FIG. 6, in the gap sensor 16, a material composite structure composed of a capacitive measuring element / sensor element 2 and a circuit board 3 serving as a carrier 3 is also formed, wherein the material composite structure has a hydrocarbon ceramic laminate and a copper surface and / or copper traces.

[0045] The gap sensor 16 specifically has two sensor elements 2a, 2b, which are designed in the circuit board 3. The sensor element 2a measures in one direction (upward in the figure), and the other sensor element 2b measures in the opposite direction (downward in the figure). Thus, the width of the gap can be measured by measuring the distance from one side of the gap and simultaneously measuring the distance from the second side of the gap and thereby determining the width of the gap.

[0046] The sensor 16 has no housing, but rather consists of the aforementioned material composite structure composed only of the sensor elements 2a, 2b and the circuit board 3 in the measurement area. This can be achieved based on the good and stable mechanical properties of the hydrocarbon ceramic laminate. In the connection area 17, the two sensor elements 2a, 2b are respectively in contact connection with the three-axis wires 5a, 5b in a known manner. Additionally, in order to mechanically fix or position the sensor 16, two threaded holes 18a, 18b or through holes are arranged on or constructed in the circuit board 3. The entire connection area 17 including the threaded holes 18a, 18b is injection-molded and coated with a hot-melt adhesive (fusible plastic) 19. This is used for mechanical fixation on the one hand and for sealing to prevent the intrusion of dust and liquid on the other hand and serves as an alternative to the housing. However, other injection molding methods can also be used in addition to the hot-melt adhesive. Figure 1 The sensor 16 is an example of such a sensor 16 that can be flexibly designed. The circuit board 3 together with the connection area 17 and the wires 5a, 5b forms a fully functional and very thin capacitive sensor 16, which has extremely good performance compared to similar sensors for monitoring the gap between two conductive objects. The thickness of such a sensor can be, for example, in the range of 0.5 mm to 1.0 mm in the single-layer structure of the hydrocarbon ceramic laminate, preferably 0.8 mm.

[0047] The gap sensor 16 with the three-axis plugs 14a, 14b is shown in a three-dimensional overall view.

[0048] Figure 4 In

[0049] In Figure 5The fourth embodiment of sensor 1 according to the present invention is shown (A: cross-sectional view through the central axis, B: cross-sectional view of the side view with mounting holes, C: top view), and the sensor is composed only of the circuit board 3 together with the sensor element and the already integrated mounting holes 18a, 18b, 18c, 18d and the conductors 5, and there is no additional housing. Sensor 1 has a multi-layer hydrocarbon ceramic laminate. The middle (core) layer has a thickness of approximately 1.5 mm. Three layers with a thickness of approximately 0.5 mm are laminated on the lower side and the upper side of the middle layer respectively, so as to achieve a total thickness of approximately 5 mm for the sensor. The mounting holes 18a, 18b, 18c, 18d can be manufactured by drilling, milling or other methods suitable for the circuit board 3.

[0050] Through the possibility of also performing three-dimensional milling and processing on the circuit board 3, a capacitive distance sensor can also be formed in a flat configuration here, and the capacitive distance sensor already provides the mounting possibility without additional components. If instead of the round conductors 5 in the cross-section as shown in Figure 6 flat conductors 20 are used as shown, a particularly flat configuration can be achieved.

[0051] In Figure 7 a sixth embodiment of the sensor in the form of an eddy current sensor 21 according to the present invention is shown in a three-dimensional overall view as a flat sensor. The sensor element 22 is composed of coils 23 arranged on the carrier 3. Coaxial conductors 24a, 24b with coaxial plugs 25a, 25b are used here. As in Figure 1 the first embodiment shown, in this flat sensor 21, a material composite structure composed of the sensor element 22 in the form of coils 23 and the circuit board 3 serving as the carrier 3 is also formed, wherein the material composite structure has a hydrocarbon ceramic laminate and copper windings and / or copper conductors.

[0052] Figure 8 The structure of the hydrocarbon ceramic laminate 27 is shown in a cross-sectional view. The multi-layer glass fiber fabric 29 is embedded (laminated) into the matrix 28. The matrix 28 contains a filler 30 composed of ceramic powder with a high filling degree.

[0053] Figure 9 The inductive sensor element 2 is shown in a partial cross-sectional view (A: on the surface 31 of the single-layer hydrocarbon ceramic laminate 27, and B: embedded in the multi-layer circuit board 3 composed of hydrocarbon ceramic laminates 27a, 27b, 27c). The sensor element 2 has a measuring electrode 32 and a shielding electrode 33, and the measuring electrode and the shielding electrode are arranged circularly. In order to achieve a better shielding effect, an additional shielding electrode 34 is arranged in another layer of the circuit board and is electrically connected to the shielding electrode 33 through vias 35.

[0054] The advantageous and important aspects of embodiments of the sensor according to the invention are set forth below:

[0055] A circuit board based on a hydrocarbon ceramic laminate (in the case of a capacitively, inductively or eddy current effect-based sensor that can be flexibly designed and is cost-effective based on printed circuit board technology) can almost directly replace a conventional FR4 circuit board.

[0056] By having a coefficient of thermal expansion that matches as well as possible with the conductor material, i.e., copper, and thus also with the stainless steel for the sensor housing that may be required, the carrier material or circuit board material, which is currently offered by many circuit board manufacturers almost 1:1 like FR4, is very well suited for use in the carrier or circuit board of a sensor according to the invention under fluctuating environmental conditions. The good processability of these materials covers almost all processing methods employed in circuit board manufacturing, which makes this material more attractive for the design and application of the present invention.

[0057] The glass transition temperature, which is usually critical for FR4, exceeds 280 °C here. Up to this temperature, the hydrocarbon ceramic laminate (KKL) also has extremely stable electrical and mechanical properties, which is very desirable and helps to cost-effectively develop a capacitive sensor in a very short time. Specifically, in the case of large temperature fluctuations, the performance of the sensor is still highly predictable.

[0058]

[0059] Capacitive, inductive or eddy current effect-based sensors can be very simply and cost-effectively manufactured using this hydrocarbon ceramic laminate. Compared with sensors having a conventional FR4 circuit board, the sensors cover a significantly larger temperature range: In the layer structure, copper surfaces or copper conductors can be applied or introduced onto or into the laminate using known circuit board technology for this purpose. The copper surfaces form the electrode surfaces (measurement electrodes, shielding electrodes (so-called Guard-Elektrode) and ground planes) required for capacitive measurement or coils (primary and secondary coils if necessary), and the electrode surfaces or coils are contact-connected to the copper conductors through vias if necessary. Due to the very similar coefficients of thermal expansion Tk of the hydrocarbon ceramic laminate and the copper surface or the metal housing, no or only very small mechanical stresses are generated even at higher temperatures, and these mechanical stresses may affect the measurement or even damage the sensor.

[0060] Particularly advantageous is that the manufacturing steps commonly used in FR4 technology can be utilized with little modification. Thus, for example, it is also possible that the flexible circuit board for connecting the sensor according to the invention is laminated onto or between the layers of the hydrocarbon ceramic laminate. In this way, flat conductors for contact-connecting the sensor elements can be realized in a very simple and cost-effective manner.

[0061] To avoid repetition, other advantageous design options of the sensor according to the invention are hereby referred to the general part of the description and the appended claims.

[0062] Finally, it should be clearly pointed out that the foregoing embodiments are merely for illustrative purposes of the claimed technical solution and are not limited to these embodiments.

[0063] List of reference numerals

[0064] 1 Sensor

[0065] 2, 2a, 2b Sensor element

[0066] 3 Carrier, circuit board

[0067] 4 Housing

[0068] 5, 5a, 5b Conductor

[0069] 6 Intermediate conductor

[0070] 7 Measuring electrode

[0071] 8 Shielded conductor

[0072] 9 Metal shielding cap

[0073] 10 Shielding electrode

[0074] 11 External shielding layer

[0075] 12 Support sleeve

[0076] 13 Crimping part

[0077] 14, 14a, 14b Three-axis plug

[0078] 15a, 15b Assembly hole

[0079] 16 Gap sensor

[0080] 17 Connection area

[0081] 18a, 18b, 18c, 18d Threaded hole, assembly hole

[0082] 19 Hot melt adhesive

[0083] 20 Flat conductor

[0084] 21 Eddy current sensor

[0085] 22 Sensor element

[0086] 23 Coil

[0087] 24a, 24b Conductors

[0088] 25a, 25b Coaxial plugs

[0089] 27 Hydrocarbon ceramic laminate

[0090] 27a - 27d Hydrocarbon ceramic laminates

[0091] 28 Substrate

[0092] 29 Glass fiber fabric

[0093] 30 Filler

[0094] 31 Surface

[0095] 32 Measuring electrode

[0096] 33 Shielding electrode

[0097] 34 Shielding electrode

[0098] 35, 35a, b Through - holes.

Claims

1. A sensor (1) for distance measurement or position measurement, in particular a capacitive or inductive sensor or a sensor (1) operating based on the eddy current effect, having a carrier (3) and a sensor element (2) arranged on or integrated into the carrier (3). Characterized in that the carrier (3) has a hydrocarbon ceramic laminate (27), is designed based on the hydrocarbon ceramic laminate (27) or consists of the hydrocarbon ceramic laminate (27).

2. The sensor according to claim 1, Characterized in that the carrier (3) is designed as a circuit board (3) or has a circuit board (3).

3. The sensor according to claim 1 or 2, Characterized in that the sensor element (2) is designed as a sensor element (2) introduced or applied or etched onto or into the carrier (3) or onto or into a metal layer of the carrier, or is designed as a sensor surface introduced or applied or etched onto or into the carrier (3) or onto or into a metal layer of the carrier.

4. The sensor according to any one of claims 1 to 3, Characterized in that the sensor (1) has a layer structure composed of the hydrocarbon ceramic laminate (27) and at least one surface made of copper or metal and / or at least one copper wire or metal wire, which can be applied or introduced onto or into the hydrocarbon ceramic laminate (27).

5. The sensor according to claim 4, Characterized in that at least one surface made of copper or metal forms an electrode surface or a sensor surface for capacitive measurement.

6. The sensor according to any one of claims 1 to 5, Characterized in that the sensor (1) is arranged in a housing (4), has a housing (4) or is coupled to the housing (4).

7. The sensor according to claim 6, Characterized in that the housing (4) is made of metal and / or has at least one assembly through-hole (15, 18) and / or at least one assembly element.

8. The sensor according to any one of claims 1 to 7, Characterized in that the sensor (1) or the connection area (17) of the sensor (1) has an injection-molded coating structure or a housing manufactured by injection molding technology.

9. The sensor according to any one of claims 1 to 8, Characterized in that the sensor element (2) is contact-connected to an evaluation electronic device through a coaxial or triaxial wire (5).

10. The sensor according to any one of claims 1 to 9, Characterized in that the carrier (3) has at least two sensor elements (2a, 2b) measuring in different directions.

11. The sensor according to claim 10, Characterized in that the sensor is a gap sensor, and the gap sensor has sensor elements (2a, 2b) measuring in opposite directions.

12. The sensor according to any one of claims 1 to 11, Characterized in that The sensor (1) or the carrier (3) has a multi-layer hydrocarbon ceramic laminate (27).

13. The sensor according to any one of claims 1 to 12, characterized in that one or more glass fiber fabrics (29) are embedded in the hydrocarbon ceramic laminate (27).

14. The sensor according to any one of claims 1 to 13, characterized in that the hydrocarbon ceramic laminate (27) has at least one filler (30), preferably ceramic powder, and more preferably ceramic powder with a high degree of filling.

15. The sensor according to any one of claims 1 to 14, characterized in that the sensor element (2) has a shielding electrode (33) in one layer of the hydrocarbon ceramic laminate (27), and the sensor (1) or the carrier (3) has an additional shielding electrode (34) in another layer of the hydrocarbon ceramic laminate (27).

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