Measuring device with cylindrical monopole antenna

Abstract

A measuring device, as a liquid level measuring device, a pressure measuring device, a temperature measuring device or a flow measuring device, for process automation in industrial or private environments, comprises a sensor device for collecting liquid level measuring data, pressure measuring data, temperature measuring data or flow measuring data, and a cylindrical monopole antenna for transmitting the measurement data to an external receiver. A battery and / or one or more circuit boards are / is arranged in the monopole antenna.

Description

[0001] Cross-reference to related applications

[0002] Priority is claimed in German Patent Application No. 10 2023206 601.7, filed on July 12, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This invention relates to measuring device technology in industrial and home environments. In particular, this invention relates to a measuring device with a cylindrical monopole antenna, a cylindrical monopole antenna, and the use of the cylindrical monopole antenna in a measuring device. Background Technology

[0004] In measuring devices used for process automation in industrial or home environments, especially self-powered sensors, the placement of the antenna inside the housing often leads to degraded transmission and reception performance, thus requiring higher energy for wireless communication. In particular, the energy storage device and its connecting wires or other circuit boards, due to their large size and proximity to the antenna, often generate interference, affecting the antenna's radiation performance. Furthermore, when using SMT chip antennas on small or circular circuit boards, achieving high efficiency in lower cellular communication frequency bands is generally difficult. Summary of the Invention

[0005] In this context, the object of the present invention is to provide a measuring device that has good transmission performance when transmitting measurement data to an external receiver.

[0006] This objective is achieved through the features of the independent claims. Further improvements to the invention are derived from the dependent claims and the following description of embodiments.

[0007] A first aspect of the invention relates to a measuring device configured for process automation in an industrial or domestic environment, the measuring device being constructed as a liquid level measuring device. It includes a sensor device configured to acquire liquid level measurement data, and a cylindrical monopole antenna for transmitting the liquid level measurement data to an external receiver. One or more batteries or rechargeable power supplies and / or circuit boards and / or radar antenna horns are disposed within the internal space of the cylindrical monopole antenna.

[0008] This measuring device can be designed as a field device in automation technology. It may include a plastic or metal housing with an opening, and an electronic unit disposed inside the housing, the electronic unit including at least one circuit board. The antenna is designed to transmit and receive electromagnetic waves having at least one predetermined wavelength, wherein the antenna is oriented such that it can transmit electromagnetic waves through the housing or the housing opening, and can receive electromagnetic waves from the direction of the housing or the housing opening. Through this antenna, a wireless communication connection can be established between the electronic unit and a transmitting / receiving unit disposed outside the field device housing.

[0009] The term "process automation in industrial environments" can be understood as a subfield of technology that involves measures to operate machines and equipment without human intervention. One goal of process automation is to automate the synergistic interaction between various components of a plant in industries such as chemical, food, pharmaceutical, petroleum, paper, cement, shipping, or mining. To this end, various sensors can be used, specifically tailored to the particular requirements of process industries, such as mechanical stability, tolerance to contamination, and adaptability to extreme temperatures and pressures. The measurements from these sensors are typically transmitted to a control center, where process parameters such as level, limits, flow rate, pressure, or density are monitored, and the settings of the entire plant can be adjusted manually or automatically.

[0010] One subfield of process automation in industrial environments involves the automation of equipment logistics and supply chain logistics. Logistics automation, utilizing distance and angle sensors, can automate processes within or outside buildings, or within a single logistics system. Typical applications include airport baggage and cargo handling systems, traffic monitoring (such as toll collection systems), retail, parcel distribution, or building security (such as access control). What these examples have in common is that their respective application scenarios require the ability to identify the presence of a target and accurately measure its size and location. For this purpose, sensors based on optical measurement methods, such as lasers, LEDs, 2D cameras, or 3D cameras, can be used. These sensors can perform distance measurements based on the time-of-flight (ToF) principle.

[0011] Another subfield of process automation in industrial environments involves factory / manufacturing automation. Related applications are widespread across various industries, such as automotive manufacturing, food production, pharmaceuticals, or more generally, packaging. The goal of factory automation is to automate product manufacturing through machines, production lines, and / or robots—that is, to complete the production process without human intervention. The sensors used in this process, and their requirements for measurement accuracy in detecting the position and size of objects, are similar to those mentioned earlier in logistics automation.

[0012] The terms used in the claims should be interpreted as broadly and reasonably as possible in accordance with the foregoing description. For example, the articles “ein” or “der” used when introducing an element should not be construed as excluding the existence of multiple elements of that class. Similarly, the use of “or” should be interpreted as including multiple elements, so mentioning “A or B” does not exclude “A and B” unless it is obvious from the context or the foregoing description that it refers to only one of A or B. Furthermore, the term “at least one A, B, and C” should be understood as selecting one or more elements from a group consisting of A, B, and C, and should not be construed as selecting at least one of A, B, and C, whether A, B, and C are related as a category or otherwise. Further, mentions of “A, B, and / or C” or “at least one A, B, or C” should be understood to include any of the following: a single A, a single B, or a single C, any combination of A and B, or a combination of A, B, and C.

[0013] Another aspect of the invention relates to a measuring device configured for process automation in industrial or domestic environments. This measuring device also includes the aforementioned components (sensor device, cylindrical monopole antenna).

[0014] Another aspect of the invention relates to a measuring device configured for process automation in an industrial or home environment, the measuring device comprising a sensor device for acquiring temperature measurement data and the aforementioned cylindrical monopole antenna.

[0015] Another aspect of the invention relates to a measuring device configured for process automation in an industrial or home environment, the measuring device comprising a sensor device for acquiring flow measurement data and the aforementioned cylindrical monopole antenna.

[0016] Cylindrical monopole antennas offer higher efficiency compared to existing structures. By placing the battery or other components inside the antenna, the impact on the antenna's radio frequency performance caused by interference, reflection, or shielding can be reduced.

[0017] According to another embodiment of the invention, the cylindrical monopole antenna tapers at one end facing the process and / or the other end facing away from the process.

[0018] According to another embodiment of the present invention, the measuring device includes a high-frequency circuit board disposed outside the cylindrical monopole antenna and configured to generate an antenna signal for transmission.

[0019] According to another embodiment of the present invention, the cylindrical monopole antenna is mounted on or fixed to a high-frequency circuit board.

[0020] According to another embodiment of the present invention, a high-frequency circuit board constitutes the pole of a cylindrical monopole antenna.

[0021] According to another embodiment of the present invention, the inner diameter of the cylindrical monopole antenna is the same as the outer diameter of the battery or battery pack.

[0022] According to another embodiment of the present invention, the measuring device further includes a contact pin coaxially arranged on a cylindrical monopole antenna for connecting the positive terminal of the battery to a high-frequency circuit board.

[0023] According to another embodiment of the invention, the measuring device includes a circuit board disposed within the internal space of a cylindrical monopole antenna. A battery may be mounted on this circuit board.

[0024] According to another embodiment of the present invention, the measuring device includes a plastic housing in which a cylindrical monopole antenna and a sensor device are disposed. Preferably, the plastic housing is a closed and sealed structure.

[0025] Another aspect of the invention relates to a cylindrical monopole antenna, as described above and below, configured to transmit measurement data of a measuring device to an external receiver, wherein a battery and / or one or more circuit boards are disposed within the internal space of the cylindrical monopole antenna.

[0026] Another aspect of the invention relates to the use of the cylindrical monopole antenna described above and below in a measuring device for process automation in an industrial or home environment, for transmitting measurement data from the measuring device to an external receiver.

[0027] Another aspect of this disclosure relates to using the cylindrical monopole antenna described above and below in process automation measurement devices in industrial or private environments to transmit measurement data from the measurement device to an external receiver.

[0028] The embodiments of the present invention will now be described with reference to the accompanying drawings. In the following description of the drawings, the same reference numerals are used to denote the same or similar elements. The drawings are schematic illustrations and are not drawn to scale. Attached Figure Description

[0029] Figure 1 illustrates a plurality of measuring devices and an external receiver according to one embodiment.

[0030] Figure 2 shows a cross-sectional view of a measuring device according to one embodiment.

[0031] Figure 3 shows a cross-sectional view of a measuring device according to another embodiment.

[0032] Figure 4 shows a front view and a side view (diagrammatic cross-section) of a measuring device according to one embodiment.

[0033] Figure 5 shows a top view of a high-frequency circuit board according to one embodiment.

[0034] Figure 6 shows the impedance matching simulation results achievable by the cylindrical monopole antenna of the measuring device according to one embodiment. Detailed Implementation

[0035] Figure 1 shows multiple measuring devices 100, 400 and an external receiver 300 in the form of a display and control unit.

[0036] The external receiver 300 can communicate with the cloud 500 or directly with the measuring devices 100 and 400 and receive measurement data from them.

[0037] The measuring device can be configured as a liquid level measuring device 100, a flow rate measuring device 100, a pressure measuring device 400, or a temperature measuring device 100, and all include a cylindrical monopole antenna 200 and a sensor device 101. For the pressure measuring device, the sensor device 101 is a pressure measuring unit; for the liquid level measuring device, the sensor device 101 is, for example, a radar chip with an antenna; for the temperature measuring device, the sensor device 101 is a temperature measuring unit; and for the flow rate measuring device, the sensor device 101 is a flow rate measuring unit.

[0038] Liquid level measuring devices can be configured as radar liquid level measuring devices, for example, and emit radar signals at frequencies of 80 GHz or higher (or lower).

[0039] Figure 2 shows a cross-sectional view of the measuring devices 100 and 400 according to one embodiment. The antenna 2 used is a monopole antenna. Instead of being constructed as a wire, the antenna is designed as a cylindrical structure with sufficient cavity to accommodate components such as batteries, battery connectors, or circuit boards. Because the internal space is a field-free region (Faraday cage), the components within it do not affect the electromagnetic fields emitted or received by the antenna. To maximize the antenna's efficiency when used in cellular communication bands such as NB-IoT, LTE-M, LPWAN, and LoRaWAN, structural improvements are required compared to conventional monopole antennas.

[0040] As the diameter of the cylindrical base plate of a monopole antenna increases, its capacitive load can cause detuning, especially in high-frequency bands. To address this, the lower part of the antenna is designed with a frustum-shaped conical structure, which can also be used as a parameter to improve impedance matching. Furthermore, a short-circuit connection is provided from the antenna housing to the grounding portion of the high-frequency circuit board 10, similar to a known PIFA antenna, providing additional impedance matching adjustment. Through this grounding connection, the negative terminal of the battery can be connected to the high-frequency circuit board without interference. The positive terminal of the battery is guided coaxially within the high-frequency feed, thus having no significant impact on system performance.

[0041] An important aspect is integrating components such as batteries and circuit boards into the interior of antenna 2, thereby avoiding interference with the antenna's radiation characteristics and achieving the highest possible antenna efficiency.

[0042] In principle, the measuring device is a self-powered sensor, i.e., a battery-powered measuring device. The measurement data it collects can be transmitted to the control center via a wireless communication interface in a predetermined time sequence. Antenna efficiency has a decisive impact on battery life because when antenna efficiency is too low, the power required for wireless communication increases significantly.

[0043] Figure 2 illustrates a measuring device according to one embodiment, wherein the required components are housed within a dustproof and waterproof plastic housing 1. Batteries and their connecting wires are preferably integrated within the cylindrical cavity of the antenna 2, as these are conductive components that will affect the antenna's electromagnetic field. In the illustrated embodiment, five batteries 4 are, as an example, combined in a battery holder 5 and connected to a circuit board 6 located on the edge of a cone via cable connectors or other means. Depending on requirements and available mounting height, additional circuit boards 6' may also be installed inside the cylinder. The same applies to measuring units 3 or 3' (not described in detail), which may be located inside and / or outside the antenna 2. Measuring unit 3' may, for example, include a radar antenna horn. Batteries may also be arranged within measuring unit 3, which is located outside the cylindrical cavity. Due to capacitive loading, the lower end of the monopole antenna 2 is designed to be tapered and mounted at the center of the high-frequency circuit board 10. The antenna is secured to the high-frequency circuit board by a plastic ring 7 with a support structure, while the housing 1 provides mechanical support.

[0044] Figure 3 illustrates a structure according to a simplified embodiment, in which a single D-type (monocell) battery 4 is mounted. Preferably, the diameter of the antenna 2 is designed so that the battery 4 can be supported against the cylindrical wall of the monopole antenna 2. A circuit board 8 located inside the antenna is connected to the positive terminal of the battery 4, and the electrode is shielded and connected to a high-frequency circuit board 10 via a contact pin 9. The circuit board 8 may also include simple circuit elements, such as reverse connection protection or current limiting circuitry, to reduce the occurrence of malfunctions.

[0045] The high-frequency circuit board 10 contains all the circuit elements used for wireless communication. The high-frequency circuit board 10 also forms the pole of a monopole antenna.

[0046] The negative terminal of the battery is connected to the conductive cover 5 via a spring contact 11. This conductive cover can be screwed into the antenna cylinder, for example, to simultaneously secure the battery. Of course, other securing methods can also be used; the key is to ensure electrical contact between the battery 4 and the antenna 2.

[0047] Antenna 2 is fixed to the center of the high-frequency circuit board 10 by a plastic ring with a support structure, thereby maintaining a constant distance from the housing 1. As a result, the antenna forms a circular radiation pattern in the azimuth direction.

[0048] At the bottom, antenna 2 tapers in a cone shape towards the high-frequency circuit board 10 to reduce capacitive load relative to ground. Adjusting the diameter of the lower end of the cone simultaneously improves the impedance matching performance of the antenna within its operating frequency band.

[0049] Figure 4 shows two more detailed views of the connection between antenna 2 and high-frequency circuit board 10. The positive terminal 4′ of battery 4 is directly introduced into high-frequency circuit board 10 coaxially via contact pin 9 through feed structure 13. To achieve isolation to ground, air insulation can be used inside the cylindrical feed structure 13, or a plastic body 15 can be filled inside the cavity of feed structure 13. The plastic body 15 provides more stable support for contact pin 9 and simultaneously hermetically shields battery 4 inside the antenna from external environmental influences.

[0050] The transmitted signal is transmitted to the antenna via two connecting pins 14. A shorting plate 12, similar to that of a known PIFA antenna, is located below the conical base of antenna 2 to establish a current path to the circuit board's ground plane. The negative terminal of the battery is guided to the circuit board via contact pin 16, which also provides an additional way to improve antenna matching characteristics.

[0051] In order to achieve optimal antenna impedance matching in, for example, the low-frequency and high-frequency bands of LTE, the contact pins 16 of the short-circuit board 12 are preferably connected by a short-circuit transmission line.

[0052] Figure 5 again shows the connection structure between the antenna and the circuit board separately. As can be seen in the figure, wire 17 is short-circuited through grounding via 19. The length of wire 17 to contact pin 16 determines the effective impedance used for antenna tuning.

[0053] Alternatively, an inductor can be placed between the contact pin 16 and the ground, and matching adjustment can be achieved by adjusting the inductance value.

[0054] A 50-ohm transmission line 18 is provided on the opposite side for transmitting high-frequency signals to the antenna. This signal is transmitted via two connecting pins 14, which are connected to a connecting ring 20. Inside the connecting ring 20, through holes for mounting contact pins 9 are visible. It is theoretically possible to introduce multiple signals into the antenna. In this case, an insulator can be provided to accommodate these connecting pins and pressed into the feed cylinder along with them.

[0055] Figure 6 shows the simulation results for the sensor shown in Figure 2. The sensor is installed in a sealed PTFE housing with an overall diameter of 93 mm and a total length of 150 mm. The achievable impedance matching results were calculated using electromagnetic field simulation software. The simulation results, shown in Figure 6, are the antenna matching curves, demonstrating excellent S11 values ​​(≤ -14 dB, corresponding to a voltage standing wave ratio (VSWR) ≤ 1.5) at both frequency band boundaries. Therefore, the antenna efficiency can reach over 90% in both frequency bands. Claims (as amended under Article 19 of the Treaty) 1. A measuring device configured for process automation in an industrial or domestic environment, the measuring device comprising: Sensor devices (101, 3) are configured to collect liquid level measurement data; A cylindrical monopole antenna (2, 200) is configured to transmit the liquid level measurement data to an external receiver (300). The cylindrical monopole antenna contains a battery (4) and / or a circuit board (6) and / or a radar antenna horn (3'). 2. A measuring device configured for process automation in an industrial or domestic environment, the measuring device comprising: Sensor devices (101, 3) are configured to collect pressure measurement data; A cylindrical monopole antenna (2, 200) is configured to transmit the pressure measurement data to an external receiver (300). A battery (4) and / or a circuit board (6) are disposed in the internal space of the cylindrical monopole antenna. 3. A measuring device configured for process automation in an industrial or domestic environment, the measuring device comprising: Sensor devices (101, 3) are configured to collect temperature measurement data; A cylindrical monopole antenna (2, 200) is configured to transmit the temperature measurement data to an external receiver (300). A battery (4) and / or a circuit board (6) are disposed in the internal space of the cylindrical monopole antenna. 4. A measuring device configured for process automation in an industrial or domestic environment, the measuring device comprising: Sensor devices (101, 3) are configured to collect flow measurement data; A cylindrical monopole antenna (2, 200) is configured to transmit the flow measurement data to an external receiver (300). A battery (4) and / or a circuit board (6) are disposed in the internal space of the cylindrical monopole antenna. 5. The measuring device according to any one of the preceding claims, The cylindrical monopole antenna (2, 200) tapers at its end facing the process end or away from the process end. 6. The measuring device according to any one of the preceding claims, wherein the measuring device further comprises: A high-frequency circuit board (10) is disposed outside the cylindrical monopole antenna (200) and configured to generate the transmitted antenna signal. 7. The measuring device according to claim 6, The cylindrical monopole antenna (2, 200) is mounted on the high-frequency circuit board (10). 8. The measuring device according to claim 6 or 7, The high-frequency circuit board (10) forms the pole of the cylindrical monopole antenna (200). 9. The measuring device according to any one of the preceding claims, A battery (4) is provided in the internal space of the cylindrical monopole antenna. The inner diameter of the cylindrical monopole antenna (2, 200) is the same as the outer diameter of the battery (4). 10. The measuring device according to any one of claims 4 to 7, wherein the measuring device further comprises: A contact pin (9) is coaxially arranged on the cylindrical monopole antenna (2, 200), wherein a battery (4) is disposed in the internal space of the cylindrical monopole antenna, and the contact pin (9) is used to connect the positive terminal of the battery (4) to the high-frequency circuit board (10). 11. The measuring device according to any one of the preceding claims, wherein the measuring device further comprises: Circuit board (6), the circuit board (6) is disposed in the internal space of the cylindrical monopole antenna (2, 200), wherein a battery (4) is disposed in the internal space of the cylindrical monopole antenna and the battery is supported on the circuit board (6). 12. The measuring device according to any one of the preceding claims, further comprising: A plastic housing (1) in which the cylindrical monopole antenna (2, 200) and the sensor device (101, 3) are disposed. 13. A cylindrical monopole antenna (2, 200) configured to transmit measurement data of a measuring device to an external receiver (300). The cylindrical monopole antenna contains a battery (4) and / or a circuit board (6) and / or a radar antenna horn (3'). 14. Use of the cylindrical monopole antenna (2, 200) according to claim 13 in a measuring device for process automation in an industrial or home environment, the use being for transmitting measurement data from the measuring device to an external receiver (300).

Claims

1. A measuring device configured for process automation in an industrial or domestic environment, the measuring device comprising: Sensor devices (101, 3) are configured to collect liquid level measurement data; A cylindrical monopole antenna (2, 200) is configured to transmit the liquid level measurement data to an external receiver (300). The cylindrical monopole antenna contains a battery (4) and / or a circuit board (6) and / or a radar antenna horn (3').

2. A measuring device configured for process automation in an industrial or domestic environment, the measuring device comprising: Sensor devices (101, 3) are configured to collect pressure measurement data; A cylindrical monopole antenna (2, 200) is configured to transmit the pressure measurement data to an external receiver (300). A battery (4) and / or a circuit board (6) are disposed in the internal space of the cylindrical monopole antenna.

3. A measuring device configured for process automation in an industrial or domestic environment, the measuring device comprising: Sensor devices (101, 3) are configured to collect temperature measurement data; A cylindrical monopole antenna (2, 200) is configured to transmit the temperature measurement data to an external receiver (300). A battery (4) and / or a circuit board (6) are disposed in the internal space of the cylindrical monopole antenna.

4. A measuring device configured for process automation in an industrial or domestic environment, the measuring device comprising: Sensor devices (101, 3) are configured to collect flow measurement data; A cylindrical monopole antenna (2, 200) is configured to transmit the flow measurement data to an external receiver (300). A battery (4) and / or a circuit board (6) are disposed in the internal space of the cylindrical monopole antenna.

5. The measuring device according to any one of the preceding claims, in, The cylindrical monopole antenna (2, 200) tapers at its end facing the process end or away from the process end.

6. The measuring device according to any one of the preceding claims, wherein the measuring device further comprises: A high-frequency circuit board (10) is disposed outside the cylindrical monopole antenna (200) and configured to generate the transmitted antenna signal.

7. The measuring device according to claim 6, in, The cylindrical monopole antenna (2, 200) is mounted on the high-frequency circuit board (10).

8. The measuring device according to claim 6 or 7, in, The high-frequency circuit board (10) forms the pole of the cylindrical monopole antenna (200).

9. The measuring device according to any one of the preceding claims, in, The inner diameter of the cylindrical monopole antenna (2, 200) is the same as the outer diameter of the battery (4).

10. The measuring device according to any one of claims 4 to 7, wherein the measuring device further comprises: Contact pin (9), which is coaxially arranged on the cylindrical monopole antenna (2, 200), is used to connect the positive terminal of the battery (4) to the high-frequency circuit board (10).

11. The measuring device according to any one of the preceding claims, wherein the measuring device further comprises: Circuit board (6), the circuit board (6) is disposed in the internal space of the cylindrical monopole antenna (2, 200), and the battery is supported on the circuit board (6).

12. The measuring device according to any one of the preceding claims, further comprising: A plastic housing (1) in which the cylindrical monopole antenna (2, 200) and the sensor device (101, 3) are disposed.

13. A cylindrical monopole antenna (2, 200) configured to transmit measurement data of a measuring device to an external receiver (300). in, A battery (4) and / or a circuit board (6) and / or a radar antenna horn (3') are disposed in the internal space of the cylindrical monopole antenna.

14. Use of the cylindrical monopole antenna (2, 200) according to claim 13 in a measuring device for process automation in an industrial or home environment, the use being for transmitting measurement data from the measuring device to an external receiver (300).

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