Device and method for operating a sensor

Abstract

The invention relates to a sensor (1) comprising a sensor unit (2) and a sensor housing, the sensor housing (3) being detachably connected to the sensor unit (2) and designed to protect the sensor unit (2) against environmental conditions. The sensor (1) is characterized in that the sensor housing (3) comprises an energy-converting unit (5, 9, 12) which is designed to provide electrical energy required for operating the sensor unit (2) by converting external energy into electrical energy.

Description

[0001] Description

[0002] Device and method for operating a sensor

[0003] The invention relates to a sensor comprising a sensor unit and a sensor housing, wherein the sensor housing is detachably connected to the sensor unit and is designed to protect the sensor unit from environmental conditions. Furthermore, the invention relates to a sensor housing for such a sensor. Furthermore, the invention relates to a method for operating a sensor to detect one or more measured variables. Furthermore, the invention relates to a computer program product for simulating the operating behavior of a sensor or a sensor housing.

[0004] In industrial applications, multisensors are increasingly being used on previously uninstrumented assets. They feed the so-called "second data channel" with machine data.

[0005] Because these sensors are often read wirelessly, a battery-based power supply makes sense. At the same time, the necessary battery replacement creates maintenance costs after several years. Furthermore, it is sustainable to use batteries for as long as possible, or even to achieve an indefinite battery life. Depending on the application, however, sufficient energy sources are often available at the sensor's installation location.

[0006] DE 10 2021 205 794 A1 discloses a sensor module having a protective cap configured to be attached to an electronics housing of the sensor module and, when attached to the electronics housing, to engage over a plug connection and a plug connected to the plug connection.

[0007] The invention is based on the object of specifying a sensor and an associated sensor housing which have a variable, battery-independent power supply. This object is achieved by a sensor comprising a sensor unit and a sensor housing, wherein the sensor housing is detachably connected to the sensor unit and is designed to protect the sensor unit from environmental conditions, according to claim 1. Furthermore, the object is achieved by a sensor housing for a sensor according to claim 13. Furthermore, the object is achieved by a method for operating a sensor for detecting one or more measured variables according to claim 14. Furthermore, the object is achieved by a computer program product for simulating an operating behavior of a sensor according to claim 15. Advantageous developments arise from the dependent claims.

[0008] A sensor according to the invention is characterized in that the sensor housing has an energy conversion unit which is designed to provide electrical energy required for operation of the sensor unit by converting external energy into electrical energy.

[0009] The sensor housing can, for example, be a protective cap that covers a connection or other elements of the sensor unit and protects it from harmful environmental influences. The sensor housing can completely or partially enclose the sensor unit. It is essential that the sensor housing is detachably connected to the sensor unit. For this purpose, the sensor housing can, for example, engage with the sensor unit's locking means and be connected to the sensor unit via threaded means.

[0010] The energy conversion unit accesses forms of energy provided by the environment at the sensor's location and converts them into electrical energy, which the sensor unit requires for proper (measurement) operation. By providing the sensor housing, the sensor unit can be protected from contamination, so that proper operation of the sensor is possible even when used in extremely dirty and / or dusty environments. By arranging the energy conversion unit in the removable sensor housing, the type of energy conversion can be easily and inexpensively adapted to specific conditions at the sensor's location.For example, it is possible to provide a sensor housing with the energy conversion unit of type A, a sensor housing with the energy conversion unit of type B and a sensor housing with the energy conversion unit of type C for the same sensor unit and, depending on the specific requirements of the location of use of the sensor, to connect them to the sensor unit to form the sensor.

[0011] The sensor can be a multifunctional sensor designed to measure at least a first variable and a second variable. Such sensors generally require more electrical energy than a unifunctional sensor, which is why the sensor design according to the invention is particularly advantageous here.

[0012] The sensor can have one or more process connections for measuring process variables in a process plant. Especially in a process plant, the conditions at the sensor's location can vary, which further enhances its advantages.

[0013] Within the scope of a preferred development of the invention, the energy conversion unit has at least one photovoltaic cell. The sensor housing and / or the sensor unit have a charge controller and an energy storage device for storing the electrical energy generated by the photovoltaic cell. The photovoltaic cell uses the radiant energy of the sun or a comparable radiation source (for example an LED or halogen lamp) in a manner known per se to convert it into electrical energy. The energy conversion unit provides the electrical energy, which is fed into an energy storage device via a charge controller. The charge controller and the energy storage device can be arranged in the sensor housing and / or the sensor unit.

[0014] In order to direct the sun's radiant energy to the photovoltaic cell, the sensor housing can be at least partially optically transparent to solar radiation. In other words, the sun's radiation can reach the photovoltaic cell through the correspondingly transparent sensor housing.

[0015] The photovoltaic cell can function as part of the sensor housing. In other words, the photovoltaic cell is arranged on an outer side of the sensor housing and forms the sensor housing at the corresponding location. This saves material for the sensor housing and maximizes the radiation input to the photovoltaic cell.

[0016] In a preferred embodiment of the invention, the energy conversion unit comprises at least one thermoelectric generator. The energy conversion unit provides the electrical energy, which is fed into an energy storage device via a charge controller. The charge controller and the energy storage device can be arranged in the sensor housing and / or the sensor unit.

[0017] A Peltier element can be used as a thermoelectric generator. The Peltier element can be connected to an object that is relatively cold compared to the ambient temperature at the sensor's location, or to a relatively warm object. In particular, this object can be the object at which the measured variable(s) are to be detected by the sensor. The sensor housing can be at least partially thermally conductive to enable a heat flow to the environment through the sensor housing.

[0018] The sensor housing can be made at least partially of a thermally conductive plastic. This provides the required thermal conductivity. It also does not impede the propagation of radio waves, which is advantageous when transmitting the measured value(s) detected by the sensor to external evaluation units.

[0019] Preferably, the sensor housing comprises a convector (a heat sink) which can enlarge a surface of the sensor housing relative to the environment and thus increase the heat flow, which improves the conversion of the thermal energy into electrical energy.

[0020] In a preferred embodiment of the invention, the energy conversion unit comprises at least one oscillation-electric generator. The energy conversion unit provides the electrical energy, which is fed into an energy storage device via a charge controller. The charge controller and the energy storage device can be arranged in the sensor housing and / or the sensor unit. The oscillation-electric generator can be piezoelectric, electrodynamic, inductive, or electrostatic, without being limited to these.

[0021] The above-explained object is also achieved by a sensor housing for a sensor, which sensor has a sensor unit, wherein the sensor housing is detachably connectable to the sensor unit and is designed to protect the sensor unit from environmental conditions. The sensor housing is characterized in that it has an energy conversion unit which is designed to provide the electrical energy required for operating the sensor unit by converting external energy into electrical energy when the sensor unit and the sensor housing are connected to one another.The previously formulated object is also achieved by a method for operating a sensor for detecting one or more measured variables, in which the sensor comprises a sensor unit and a sensor housing, wherein the sensor housing is detachably connected to the sensor unit and is designed to protect the sensor unit from environmental conditions, and wherein the sensor housing has an energy conversion unit which provides electrical energy required for operation of the sensor unit by converting external energy into electrical energy.

[0022] Furthermore, the object is achieved by a computer program product for simulating an operating behavior of a sensor or a sensor housing as previously explained, or for producing a sensor or a sensor housing as previously explained.

[0023] The above-described properties, features, and advantages of this invention, as well as the manner in which they are achieved, will become clearer and more readily understood in connection with the following description of the embodiments, which is explained in more detail in conjunction with the figures. They show:

[0024] FIG 1 shows a diagram of a sensor according to the invention according to a first embodiment;

[0025] FIG 2 shows a diagram of a sensor according to the invention according to a second embodiment; and

[0026] FIG 3 is a diagram of a sensor according to the invention according to a third embodiment.

[0027] FIG. 1 shows a schematic diagram of a sensor 1 according to the invention. The sensor 1 comprises a sensor unit 2 and a sensor housing 3. The sensor unit 2 is designed in a manner known per se to detect one or more measured variables, in particular process measured variables.

[0028] For this purpose, the sensor unit 2 requires electrical energy.

[0029] The sensor unit 2 and the sensor housing 3 are connected to each other by means of a screw thread. This connection 4 is detachable, meaning that the sensor housing 3 can be removed from the sensor unit 2 without damaging the sensor 1. The sensor 1 is attached to a measuring object 13, such as a pipeline, an engine, or a tank.

[0030] The sensor housing 3 has a photovoltaic cell 5, a charge controller 6 and an energy storage device 7. In an area 8, the sensor housing 3 is transparent to solar radiation so that, particularly during operation of the sensor 1 at the site of use, the solar radiation can fall on the photovoltaic cell 5. The photovoltaic cell 5, as an energy conversion unit, converts the solar radiation energy into electrical energy. This is either stored in the energy storage device 7 by the charge controller 6 or made available directly to the sensor unit 2. If there is insufficient solar radiation energy available, the charge controller 6 can draw the energy required to supply the sensor unit 2 from the energy storage device 7. This enables uninterrupted operation of the sensor 1.

[0031] FIG. 2 shows a schematic diagram of another sensor 1 according to the invention. The sensor 1 comprises a sensor unit 2 and a sensor housing 3. The sensor 1 is attached to a measurement object 13, such as a pipeline, an engine, or a tank.

[0032] The sensor unit 2 is designed in a manner known per se to detect one or more measured variables, in particular process variables. For this purpose, the sensor unit 2 requires electrical energy. The sensor unit 2 and the sensor housing 3 are connected to one another by means of a screw thread. This connection 4 is detachable, i.e., the sensor housing 3 can be removed from the sensor unit 2 without damaging the sensor 1.

[0033] The sensor housing 3 has a thermoelectric generator designed as a Peltier element 9. The Peltier element 9 is installed in a base region 10 of the sensor housing 3 and converts a heat flow into electrical energy. This heat flow is generated by a temperature difference compared to the environment. In particular, the heat of the object on which the measured variables are to be determined can be used here. The Peltier element 9, as an energy conversion unit, converts the heat energy into electrical energy. This is either stored in the energy storage device 7 by the charge controller 6 or made available directly to the sensor unit 2. The sensor housing 3 consists in a region 11 of a thermally conductive plastic in order to enable a heat flow through the sensor housing 3 to the environment.

[0034] FIG. 3 shows a schematic diagram of another sensor 1 according to the invention. The sensor 1 comprises a sensor unit 2 and a sensor housing 3. The sensor 1 is attached to a measurement object 13, such as a pipeline, an engine, or a tank.

[0035] The sensor unit 2 is designed in a manner known per se to detect one or more measured variables, in particular process variables. For this purpose, the sensor unit 2 requires electrical energy. The sensor unit 2 and the sensor housing 3 are connected to one another by means of a screw thread. This connection 4 is detachable, i.e., the sensor housing 3 can be removed from the sensor unit 2 without damaging the sensor 1.

[0036] The sensor housing 3 has an oscillation-electric generator embodied as a piezoelectric element 12. In a base region 10 of the sensor housing 3, the piezoelectric element 12 is connected to the sensor unit 2 in such a way that it can absorb vibrations of the measurement object 13 and convert them into electrical energy according to the piezoelectric effect. In the embodiment of the invention shown in FIG. 3, the sensor housing 3 is (mechanically) connected to the measurement object 13 only via the piezoelectric element 12. An electrical connection between the charge controller 6 and the measurement object 13 is designed such that it has no or negligible influence on the vibration absorption by the piezoelectric element 12.

[0037] The piezo element 12 acts as an energy conversion unit, converting the vibration energy into electrical energy. This energy is either stored in the energy storage unit 7 by the charge controller 6 or made available directly to the sensor unit 2.

[0038] The individual sensor housings 3 can be flexibly exchanged as needed at the location of the sensor 1. For this purpose, the operation of the energy conversion units 6 can be monitored and evaluated, for example, using a cloud-based functionality, in order to be able to switch to the optimal type of energy conversion unit when needed.

[0039] Although the invention has been illustrated and described in detail by the preferred embodiment, the invention is not limited to the disclosed example, and other variations may be derived therefrom by those skilled in the art without departing from the scope of the invention.

Claims

Patent claims 1. Sensor (1) comprising a sensor unit (2) and a sensor housing, wherein the sensor housing (3) is detachably connected to the sensor unit (2) and is designed to protect the sensor unit (2) from environmental conditions, characterized in that the sensor housing (3) has an energy conversion unit (5, 9, 12) which is designed to provide electrical energy required for operation of the sensor unit (2) by converting external energy into electrical energy.

2. Sensor (1) according to claim 1, which is designed as a multifunctional sensor (1) for measuring at least a first variable and a second variable.

3. Sensor (1) according to claim 1 or 2, which has one or more process connections for measuring process variables in a process plant.

4. Sensor (1) according to one of the preceding claims, wherein the energy conversion unit (5, 9, 12) comprises at least one photovoltaic cell (5), and the sensor housing (3) and / or the sensor unit (2) have a charge controller (6) and an energy store (7) for storing the electrical energy generated by the photovoltaic cell (5).

5. Sensor (1) according to claim 4, wherein the sensor housing (3) is at least partially optically transparent to solar radiation.

6. Sensor (1) according to one of the preceding claims, wherein the energy conversion unit (5, 9, 12) comprises at least one thermoelectric generator (9), and the sensor housing (3) and / or the sensor unit (2) have a charge controller (6) and an energy store (7) for storing the electrical energy generated by the thermoelectric generator (9).

7. Sensor (1) according to claim 6, wherein the thermoelectric generator (9) is a Peltier element.

8. Sensor (1) according to claim 6 or 7, wherein the sensor housing (3) is at least partially thermally conductive.

9. Sensor (1) according to one of claims 6 to 8, wherein the sensor housing (3) consists at least partially of a thermally conductive plastic.

10. Sensor (1) according to one of claims 6 to 9, wherein the sensor housing (3) comprises a convector.

11. Sensor (1) according to one of the preceding claims, wherein the energy conversion unit (5, 9, 12) comprises at least one vibration-electric generator (12), and the sensor housing (3) and / or the sensor unit (2) have a charge controller (6) and an energy store (7) for storing the electrical energy generated by the vibration-electric generator (12).

12. Sensor (1) according to claim 11, wherein the vibration-electric generator (12) is piezoelectric, electrodynamic, inductive or electrostatic.

13. Sensor housing (3) for a sensor (1) which has a sensor unit (2), wherein the sensor housing (3) is detachably connectable to the sensor unit (2) and is designed to protect the sensor unit (2) from environmental conditions, characterized in that the sensor housing (3) has an energy conversion unit (5, 9, 12) which is designed to provide electrical energy required for operation of the sensor unit (2) by converting external energy into electrical energy when the sensor unit (2) and the sensor housing (3) are connected to one another.

14. Method for operating a sensor (1) for detecting one or more measured variables, in which the sensor (1) comprises a sensor unit (2) and a sensor housing (3), wherein the sensor housing (3) is detachably connected to the sensor unit (2) and is designed to protect the sensor unit (2) from environmental conditions, and wherein the sensor housing (3) has an energy conversion unit (5, 9, 12) which provides electrical energy required for operating the sensor unit (2) by converting external energy into electrical energy.

15. A computer program product for simulating an operating behavior of a sensor (1) or a sensor housing (3) according to one of claims 1 to 13, or for producing a sensor (1) or a sensor housing (3) according to one of claims 1 to 13.

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