Measuring device

Abstract

The invention relates to a measuring device (100) having first electronics (1), second electronics (3), and a housing (5) having a first chamber (7) for receiving the first electronics (1), a second chamber (9), and a passage (11) connecting the first chamber (7) to the second chamber (9). A plug connection (13) is inserted in the passage (11), the first component (15) of which plug connection comprises a plug (19) of the first electronics (1), and the second component (17) of which plug connection comprises a socket (23), in the interior (29) of which socket a front region (31) of the plug (19) is inserted in a mechanically accurately fitting manner, which front region has a plurality of regions (37, 37') arranged asymmetrically distributed around the front region (31) on the outside, which regions are each designed as a projection extending parallel to a longitudinal axis of the plug (19) or as a notch extending parallel to the longitudinal axis of the plug (19). The second component (17) comprises a feedthrough (25), through which connecting elements (27) run, the first ends of which pointing into the interior (29) of the socket (23) are connected to connection elements (33) of the first electronics (1) integrated in the plug (19) and the second ends of which are connected to the second electronics (3).

Description

[0001] measuring device

[0002] The invention relates to a measuring device with a housing and a first electronics unit arranged in a first chamber of the housing, which is connected to a second electronics unit via an electrical feedthrough arranged in a passage between the first chamber and a second chamber.

[0003] Measuring instruments, such as flow meters, pressure gauges or level gauges, are used in a variety of different applications, such as in the chemical industry, the food industry, as well as in water treatment plants, e.g. in sewage treatment plants, to measure various types of quantities.

[0004] These measuring instruments typically comprise a measuring device with a sensor for the metrological acquisition of the measured quantity(ies) and measuring electronics that provide a measurement signal corresponding to the measured quantity. The measurement signal is usually an analog signal, such as a raw signal generated by an electromechanical or electrochemical transducer in the sensor. The measuring electronics are generally connected to a higher-level electronics unit that supplies the measuring device with power and / or receives, digitizes, processes, evaluates, and / or determines and provides measured values ​​of the measured quantity(ies) based on the measurement signals.

[0005] To facilitate easy maintenance, repair, or even replacement of individual components of the measuring device, it is advantageous to connect the higher-level electronics to the measuring electronics of the measuring system via a detachable connection. However, analog measurement signals are generally sensitive to interference. This is especially true for measurement signals from capacitive sensors. Consequently, even small relative movements of electrically conductive elements arranged along the signal transmission path from the measuring electronics to the higher-level electronics can lead to changes in the contact resistance of the electrically conductive connection between the measuring electronics and the higher-level electronics. Such relative movements can be caused, for example, by vibrations occurring at the installation site.Changes in contact resistance can lead to impairments of the measurement signals to be transmitted, which can adversely affect the achievable measurement accuracy.

[0006] In industrial metrology, as well as in the process and automation industries, measuring instruments are used, among other places, in potentially explosive atmospheres. Examples include flour silos, gas stations, chemical plants, and other locations where explosive gases may be present. Measuring instruments used in potentially explosive atmospheres are subject to special safety requirements. These requirements aim to prevent the formation of sparks that could potentially trigger an explosion, or to prevent a spark originating inside an enclosed space from affecting the surrounding environment. These objectives can be achieved in various ways, which are described in the relevant European standards as types of ignition protection.

[0007] Explosion protection according to a type of ignition protection known as flameproof enclosure (Ex-d) can be achieved by having measuring instruments have a flameproof housing that prevents an explosion occurring inside the housing in the event of a fault from being transmitted to the outside.

[0008] Furthermore, explosion protection according to an intrinsic safety (Ex-i) type of ignition protection can be achieved, for example, by ensuring that the current, voltage, and power in a measuring device remain below a predetermined limit at all times. These three limit values ​​are chosen so that the maximum heat generated in the event of a fault, such as a short circuit, is insufficient to produce an ignition spark.

[0009] In this context, EP 0 945 714 A1 describes an electronic device whose housing has a connection compartment designed according to protection class Ex-d and a separate electronics compartment. A circuit is arranged in the connection compartment and is connected via a pressure-resistant bushing to electronics located in the electronics compartment, which are designed according to protection class Ex-i. The circuit and the electronics are preferably each connected to the bushing via a plug connector.

[0010] Furthermore, DE 10 2022 114 039 A describes a measuring device in which the conductors of a connecting cable attached to a sensor element are connected to contact elements of a feedthrough element by means of a material bond. The feedthrough element comprises a hollow cylindrical sleeve in which a base body is arranged, in which the contact elements are embedded. The feedthrough element is designed, for example, as a component of a multipin connector system via which the sensor element can be connected to a measuring circuit.

[0011] Even when using connectors, relative movements of electrically conductive elements along the signal transmission path, particularly due to vibrations at the installation site, can lead to changes in transmission resistance and thus also to impairments of interference-sensitive signals transmitted via the connector. The risk of such relative movements can be reduced, for example, by measures to secure the electronics and / or the connector components. However, this regularly requires additional components, such as screws and / or springs, which must be stocked and installed. This leads to an increase in manufacturing costs and production effort. With regard to signal transmission quality, it may be more advantageous to connect electrical leads directly to contact pins passing through the bushing using a joining process.Suitable joining processes for this purpose, such as soldering, welding, or crimping, generally have to be carried out manually. This leads to correspondingly high manufacturing costs and can potentially result in variations in the quality of manually produced joints.

[0012] It is an object of the invention to provide a measuring device, particularly suitable for use in potentially explosive atmospheres, with electronics detachably connected to one another via an electrical feedthrough, enabling high-quality signal transmission via the feedthrough.

[0013] The invention comprises a measuring device with first electronics, second electronics, and a housing with a first chamber for receiving the first electronics, a second chamber, and a passage connecting the first chamber to the second chamber, wherein: a detachable plug connection is inserted into the passage, comprising a first component and a complementary second component, the first component comprising a plug of the first electronics, the second component comprising a socket in the interior of which a front area of ​​the plug is mechanically fitted, the socket having several asymmetrically distributed areas on the outside around the front area, each of which is designed as a projection extending parallel to a longitudinal axis of the plug or as a notch extending parallel to the longitudinal axis of the plug.and the second component comprises a feedthrough made of an insulator adjacent to the interior of the socket, through which electrically conductive connecting elements pass, the first ends of which pointing into the interior are connected to terminal elements of the first electronics integrated in the plug, complementary to the connecting elements, by creating the plug connection, and the second ends of which opposite the first ends are connected to the second electronics.

[0014] The asymmetrically distributed areas around the front of the connector, each designed as a protrusion or indentation, and the corresponding cross-sectional area of ​​the socket's interior, which is complementary to the cross-sectional area of ​​the front of the connector, offer the advantage that the connector can be positioned with high precision in the socket without additional components. This virtually eliminates any play in the connector's positioning within the socket, preventing relative movement of the connecting elements and the terminals integrated into the connector, which could otherwise lead to changes in the connection's transmission resistance. This results in a correspondingly high and, in particular, consistent transmission quality of signals transmitted via the connector, even under vibrations occurring at the point of use.Further developments consist of the front area having an asymmetrical cross-sectional area and the interior of the socket complementary to the plug having an asymmetrical cross-sectional area corresponding to the cross-sectional area of ​​the front area, and / or the front area of ​​the plug having three areas arranged on the outside around the plug.

[0015] Further developments provide that each area of ​​the front of the connector is designed as a projection, and / or each projection-designed area of ​​the front of the connector has a cross-sectional area with an outer contour that is rounded on the outside or circular segment-shaped.

[0016] Further developments consist of the second component being inserted into the passage in such a way that it seals the passage in a pressure-tight manner, and / or the bushing being connected to a housing area of ​​the housing that surrounds the passage on all sides on the outside by means of a pressure-tight connection or a pressure-tight connection designed as a weld.

[0017] According to a further development, the bushing has a shoulder projecting on all sides on the outside, the end face of which, facing the measuring instrument of the first chamber, rests against a stop surface of the housing facing the second chamber.

[0018] According to a further development, the first ends of the connecting elements projecting into the interior of the bushing are arranged recessed relative to one of the end faces of the bushing facing the first chamber.

[0019] A further embodiment comprises a measuring device according to the invention with a measuring device for the metrological acquisition of at least one measurand, wherein: the second electronics are designed as measuring electronics connected to or integrated in the measuring device, and / or are designed to provide an analog measurement signal corresponding to the measurand acquired by means of the measuring device, and / or the first electronics are designed to supply the second electronics and / or the measuring device with energy, to receive, digitize, process and / or evaluate measurement signals provided by the second electronics via the plug connection, and / or to determine and provide measured values ​​of the measurand(s) based on the measurement signals.

[0020] A further embodiment consists in the second electronic component being configured to provide analog signals via the connector, and the first electronic component comprising an analog-to-digital converter for digitizing the analog signals, which is arranged in an area of ​​the first electronic component directly adjacent to the connector and / or on a side of a circuit board of the first electronic component opposite the connector. A further embodiment comprises a measuring device according to the invention in which the connector has a shoulder in a rear area adjacent to its front region, projecting outwards on all sides, wherein: the shoulder, in conjunction with a seal arranged in the housing, provides a seal for an interior space surrounding the first electronic component in the first chamber or for an interior space surrounding the first electronic component in the first chamber that is filled with a potting compound.and / or wherein the first electronics in the first chamber are arranged in a cup-shaped insert or in a cup-shaped insert filled with a potting compound, the insert having a through-opening through which the front part of the plug is inserted into the socket inserted into the through-opening, and a gap existing between the shoulder of the plug and a base of the insert surrounding the through-opening on all sides is sealed by a seal.

[0021] A further development of the latter development provides that the seal is connected to the insert or formed as part of the insert, and / or the seal comprises a cylindrical area arranged in the passage opening, a sealing lip projecting radially inwards at one end of the cylindrical area and a sealing lip projecting radially outwards at the other end of the cylindrical area, wherein the inwardly projecting sealing lip is clamped between a base area of ​​the insert surrounding the passage opening on all sides and the shoulder of the plug, and the outwardly projecting sealing lip is clamped between the base area of ​​the insert surrounding the passage opening on all sides and an inner surface of the housing surrounding the passage on all sides.

[0022] Further features include the fact that the passage has a cross-sectional area of ​​less than or equal to 7 cm². 2is and / or has a diameter of less than or equal to 3 cm, the socket is made of metal or stainless steel, the connecting elements are designed as contact pins and / or are made of a nickel-iron alloy, the feedthrough is pressure-resistant and fixed in the socket and / or is designed as a glass feedthrough, the plug electrically connected to the first electronics is mechanically attached to a circuit board of the first electronics, the connecting elements comprise sleeves that each line a bore passing through the plug, the connecting elements are connected or soldered at their ends to a terminal of the first electronics arranged on the circuit board, the connecting elements are made of a soft and / or spring-elastic conductive material, a metal and / or a copper-beryllium alloy, and / or the measuring instrument is designed as a device suitable for use in potentially explosive atmospheres.

[0023] Further enhancements consist of the second component having seven connecting elements or an odd number of connecting elements, all connecting elements being arranged on the outside and / or in a circular pattern around a central area of ​​the feedthrough,

[0024] The distances between directly adjacent connecting elements are equal and / or greater than or equal to an outer dimension or an outer diameter of the connecting elements, and / or the plug has a planar surface on its end face facing the socket, surrounded on the outside by the connecting elements.

[0025] A further development consists in the fact that electrical connecting lines of the second electronics arranged in the second chamber are each connected directly to the second end of one of the connecting elements passing through the feedthrough by means of a joint, a joint produced by means of an automated joining process, and / or a joint designed as a weld, as a solder or as a crimp connection.

[0026] Furthermore, the invention comprises a method for manufacturing a measuring device according to the invention, in which the second component of the plug connection is manufactured, the second electronics are connected to the second ends of the connecting elements of the second component, the second component is inserted into the passage between the first chamber and the second chamber, and the plug connection is created by inserting the first electronics equipped with the plug into the first chamber in such a way that the front area of ​​the plug is arranged in the interior of the socket.

[0027] A further development of the method provides that the second electronics are connected to the second ends of the connecting elements of the second component by means of a method or an automated method in which the feedthrough is rotated step by step and in each rotation position one of the connecting elements is connected to the associated connecting line by means of a joining tool, which comprises a tool component that can be attached from the outside to an outside of the respective joining point and a tool component that can be attached through a gap opposite the respective joining point to an inside of the joining point.

[0028] The invention and its advantages will now be explained in more detail with reference to the figures in the drawing, which illustrate two exemplary embodiments. Identical elements in the figures are designated with the same reference numerals.

[0029] Fig. 1 shows: a measuring device with two electronics connected via a plug connection;

[0030] Fig. 2 shows: a view of a first component of the connector of Fig. 1;

[0031] Fig. 3 shows: a view of a second component of the connector of Fig. 1;

[0032] Fig. 4 shows: a sectional drawing of the second component shown in Fig. 3;

[0033] Fig. 5 shows: the plug connection of Fig. 1 in a section plane passing through a front area of ​​the first component; and

[0034] Fig. 6 shows: an alternative embodiment of the plug connection of Fig. 1 in a section plane passing through a front area of ​​the first component.

[0035] The invention relates to a measuring device 100 with a first electronics unit 1 and a second electronics unit 3. An embodiment is shown in Fig. 1.

[0036] The measuring device 100 comprises a housing 5 with a first chamber ? for receiving the first electronics 1 , a second chamber 9 and a passage 11 connecting the first chamber 7 with the second chamber 9.

[0037] The housing 5 of the measuring instrument 100, for example, is designed as a one- or multi-part housing made of a plastic, such as polycarbonate, or of a metal, such as stainless steel.

[0038] A mechanically detachable connector 13 is inserted into passage 11, via which the first electronics 1 is electrically connected to the second electronics 3. The connector 13 comprises a first component 15 and a complementary second component 17.

[0039] The first component 15 comprises a connector 19 of the first electronics unit 1. Fig. 1 shows an embodiment in which the first electronics unit 1 comprises a printed circuit board 21 populated with electronic components, and the connector 19, which is electrically connected to the first electronics unit 1, is mechanically attached to the printed circuit board 21. A view of the first component 15 formed by the connector 19 in Fig. 1 is shown in Fig. 2.

[0040] The second component 17 comprises a bushing 23 and a feedthrough 25 made of an insulator, through which electrically conductive connecting elements 27 pass. A view of the second component 17 is shown in Fig. 3. Fig. 4 shows a sectional drawing of the second component. In the illustrated example, the bushing 23 is made of a metal, such as stainless steel, and the feedthrough 25 is made of glass, for example. This embodiment offers the advantage that the feedthrough 25 can be pressure-tightly connected to the bushing 23 and the connecting elements 27 by a manufacturing process in which the molten glass, which in its liquid state surrounds the connecting elements 27 on the outside, solidifies in the bushing 23. This results in, in particular,The different coefficients of thermal expansion of the metallic bushing 23 and the feedthrough 25 also result in a highly mechanically stable fastening of the feedthrough 25 in the bushing 23, which surrounds the feedthrough 25 on all sides. Alternatively, the bushing 23 and / or the feedthrough 25 can also be made of a different material, and / or the feedthrough 25 can be fastened in the bushing 23 in a different way.

[0041] Regardless of the specific design of the second component 17, the connecting elements 27 are, for example, designed as contact pins made of an electrically conductive material, such as a metal. In this respect, contact pins made of a nickel-iron alloy are suitable, for example.

[0042] The feedthrough 25 integrated in the second component 17 adjoins an interior 29 of the socket 23, into which at least one front area 31 of the plug 19 is inserted. For this purpose, the socket 23 is designed, for example, as a sleeve closed at its end or in a middle area by the feedthrough 25.

[0043] The connecting elements 27 extending through the feedthrough 25 each have a first end pointing into the interior 29 of the socket 23 and a second end opposite the first end. The first ends of the connecting elements 27 pointing into the interior 29 are connected to terminal elements 33 of the first electronics 1 integrated into the connector 19, which are complementary to the connecting elements 27, by creating the plug connection 13. Fig. 1 shows an embodiment in which the terminal elements 33 arranged in the connector 19 comprise sleeves, each of which lines a bore extending through the connector 19, and the terminal elements 33 are connected or soldered at their ends to a terminal 35 of the first electronics 1 located on the side of the circuit board 21 facing the connector 19. The terminal elements 33 are made of an electrically conductive material, such as a metal.For this purpose, a soft and / or spring-elastic conductive material, such as a copper-beryllium alloy, is particularly suitable. Connection elements 33 made of a soft and / or spring-elastic material offer the advantage of a form-fitting and / or spring-elastic clamping of the connecting elements 27 in the connection elements 33, corresponding to the material properties.

[0044] The second ends of the connecting elements 29, opposite the first ends, are connected to the second electronics 3. According to the invention, the front region 31 of the plug 19 is inserted precisely into the socket 23. For this purpose, the front region 31 has several areas 37 arranged asymmetrically around its outer surface, each of which is designed as a projection extending parallel to a longitudinal axis of the plug 19 or as a notch extending parallel to the longitudinal axis of the plug 19.

[0045] Due to the asymmetrically arranged outer areas 37, the front area 31 has an asymmetrical cross-sectional area. Accordingly, the interior 29 of the socket 23, which is complementary to the plug 19, also has an asymmetrical cross-sectional area corresponding to the cross-sectional area of ​​the front area 31.

[0046] This design of the plug 19 and the socket 23 offers the advantage that the plug 19 can be positioned very precisely and therefore without play in the socket 23. This is illustrated in Fig. 5, which shows a sectional drawing of the connector 13 in a section plane running through the front area 31.

[0047] A further advantage is that the asymmetrical arrangement of the areas 37 of the front area 31 of the plug 19 and the complementary design of the socket 23 provide an orientation in which the plug 19 can be inserted into the socket 23. The resulting anti-rotation feature offers the advantage that related assembly errors during the manufacture of the measuring instrument 100 are eliminated.

[0048] In the embodiment shown in Figs. 1, 2 and 5, the areas 37 are each formed as projections extending radially outwards and parallel to the longitudinal axis of the front area 31.

[0049] In this embodiment, the areas 37, which are designed as projections, are such that they have a cross-sectional surface with an outer contour that is rounded or circular segment-shaped. This offers the advantage that the corresponding recesses 39, which receive the projections, can be produced in the wall area of ​​the bushing 23 surrounding the interior 29 by cost-effective mechanical machining processes, such as milling. Alternatively, the projections can also have a different cross-sectional geometry.

[0050] Fig. 6 shows, as a further embodiment, a sectional drawing of a connector 13 designed analogously to the connector 13 shown in Figs. 1 and 5 in a section plane running through the front region 31 of the connector 19. This connector differs from the embodiment previously described with reference to Figs. 1 to 5 only in that the areas 37' of the connector 19, which are arranged asymmetrically around the outside of the front region 31, are each designed as indentations extending parallel to the longitudinal axis of the front region 31. Accordingly, the wall region of the socket 23 surrounding the interior 29 of the socket 23 has radially inwardly projecting projections 41 that are complementary to the indentations in the front region 31 of the connector 19.

[0051] In both the embodiment shown in Figures 1, 2, and 5 and the embodiment shown in Figure 6, the connector 19 has three areas 37, 37' arranged asymmetrically around the outer surface of the front area 31 of the connector 19, each formed as a projection or a notch. In this case, the asymmetrical arrangement of the areas 37, 37' is achieved, for example, by arranging two of the three areas 37, 37' diametrically opposite each other, and the third area 37, 37' being arranged on the outer surface of one of the two opposing outer surfaces of the front area 31, each extending from one of the two opposing areas 37, 37' to the area 37, 37' opposite it.

[0052] Regardless of the specific design, variants of the connectors 13 described here, whose plug 19 has three areas 37, 37' arranged asymmetrically around the front area 31 of the plug 19, offer the advantage, compared to connectors whose plug has only a single projection or only a single notch, that with them, twice as precise positioning of the plug 19 in the socket 23 can be achieved with the same manufacturing tolerances.

[0053] In the manufacture of the measuring device 100, the following procedure is used, for example: the second component 17 of the connector 13 is manufactured, the second electronics 3 is connected to the second ends of the connecting elements 27 of the second component 17, and the second component 17 is then inserted through a closable opening 43 of the second chamber 9 into the passage 11 between the first chamber 7 and the second chamber 9. Subsequently, the connector 13 is created by inserting the first electronics 1, equipped with the plug 19, through a closable opening 45 of the first chamber 7 into the first chamber 7 such that the front area 31 of the plug 19 is positioned in the designated interior 29 of the socket 23.

[0054] The openings 43, 45 of the first chamber 7 and / or the second chamber 9 can be closed in different ways. For example, the opening 45 of the first chamber 7 can be closed by a closure not shown in Fig. 1, such as a housing cover or a connection housing that can be mounted on the housing 5. Alternatively or additionally, the opening 43 of the second chamber 9 can be closed by a closure not shown in Fig. 1, such as a housing cover or a sensor housing that can be mounted on the housing 5. The measuring device 100 described above, as well as its manufacturing process, exhibits the aforementioned advantages. Individual components of the measuring device 100 and / or individual process steps of the manufacturing process can optionally be used individually and / or in combination with one another.

[0055] One embodiment shown in Fig. 1 consists in the measuring device 100 comprising a measuring device 47, such as a sensor, for the metrological detection of at least one measured quantity. In this respect, the measuring device 100 is, for example, configured as a flow meter, a level meter, a pressure meter, or as a measuring device 100 for measuring at least one other measured quantity.

[0056] In this embodiment, the second electronics 3 is configured, for example, as measuring electronics connected to or integrated into the measuring device 47. One exemplary embodiment of this is that the second electronics 3 comprises or is formed by a transducer, such as an electrochemical or electromechanical transducer, such as a resistive, capacitive, electrodynamic, or piezoresistive transducer. Alternatively or additionally, the second electronics 3 is configured, for example, to provide an analog measurement signal corresponding to the measured quantity acquired by the measuring device 47 via the connector 13.

[0057] In this respect, the first electronics unit 1 is, for example, configured to supply the second electronics unit 3 and / or the measuring device 47 with energy, and / or to receive, digitize, process, and / or evaluate measurement signals provided by the second electronics unit 3 via connector 13. With regard to the evaluation of the measurement signals, the first electronics unit 1 is, for example, configured to determine and provide measured values ​​of the measured quantity(ies) based on the measurement signals.

[0058] An optional embodiment, particularly advantageous in connection with the transmission of signals sensitive to interference, such as analog measurement signals, and shown in Fig. 1, consists in the fact that electrical connecting lines 49 of the second electronics 3 arranged in the second chamber 9 are each connected directly to the second ends of the connecting elements 27 passing through the feedthrough 25 by means of a joining, such as a welding, a soldering or crimp connection.

[0059] The direct connection of the second electronic component 3, achieved through the joints, offers an advantage over an alternative embodiment in which the second electronic component is connected to the second ends of the connecting elements 27 via an additional connector component, such as a connector component designed analogously to the first component 15. This advantage is that the additional transmission resistances caused by the connection of the additional connector component are eliminated. A further optional embodiment consists of having an odd number of connecting elements 27 of the second component 17, and / or distributing all connecting elements 27 around a central area of ​​the feedthrough 25, for example, in a circular pattern, such that the distance between immediately adjacent connecting elements 27 is greater than or equal to an outer dimension, such as...an outer diameter, which is the connecting element 27. Figures 3 to 5 and Figure 6 show an embodiment in which seven connecting elements 27 are arranged at equal intervals around the longitudinal axis of the bushing 23.

[0060] When the connecting elements 29 are arranged in a circle, the complementary terminal elements 33 integrated into the connector 19 are also arranged in a circle. In this case, the connector 19 is designed, for example, such that it has a planar surface 50 on its end face facing the socket 23, surrounded on the outside by the terminal elements 33. This surface 50 offers the advantage that the connector 19 can be suction-lifted and positioned on the printed circuit board 21 during automated assembly.

[0061] The odd number of connecting elements 27, in combination with their arrangement outside the central area of ​​the feedthrough 25, offers the advantage that no connecting elements 27 pass through the central area and that each connecting element 27 has a gap between two adjacent connecting elements 27 on the opposite side of the feedthrough 25. This offers the advantage that the creation of the connections between the second ends of the connecting elements 27 and the connecting leads 49 of the second electronics 3 can be automated.

[0062] In the automated production of the joints, the process is carried out, for example, by rotating the feedthrough 25 step by step and, in each rotational position, connecting one of the connecting elements 27 to the associated connecting line 49 by means of a joining process carried out using a joining tool. As schematically shown in Fig. 5, the joining tool comprises, for example, a tool component W1 that can be attached from the outside to an outer surface of the respective joining point and a tool component W2, e.g. rod-shaped, that can be attached through the gap opposite the respective joining point to an inner surface of the joining point.

[0063] The automated production of joints, such as the aforementioned soldering, welding, or crimping connections, using a suitably designed joining tool, offers the advantage over alternative, manually performed joining methods of being significantly less prone to errors. This results in correspondingly high-quality joints with consistently reproducible quality. Alternatively or additionally to the previously described configurations, the first ends of the connecting elements 27, which project into the interior 29 of the bushing 23, are, for example, recessed relative to an end face of the bushing 23 facing the first chamber in the assembled state.

[0064] This offers the advantage when generating the plug connection 13 that the plug 19 only comes into contact with the connecting elements 27 projecting into the interior 29 of the socket 23 when the mutually complementary asymmetric cross-sectional areas of the front area 31 of the plug 19 and the interior 29 of the socket 23 ensure that the plug 19 is inserted straight, in the correct orientation with high precision, fits perfectly and is therefore free of play into the socket 23.

[0065] The mutually complementary asymmetric cross-sectional areas of the front area 31 of the plug 19 and the interior 29 of the socket 23 offer the advantage that the plug 19 can be mounted in the correct orientation without rotation, without the connecting elements 27 being visible.

[0066] Another optional embodiment, particularly advantageous in connection with the transmission of interference-sensitive analog signals, such as analog measurement signals, and shown in Fig. 1, consists in the first electronics 3 having an analog-to-digital converter (A / D) for digitizing the analog signals in an area directly adjacent to the connector 19. This offers the advantage of a correspondingly short signal transmission path along which the signals are present in analog form and are therefore more susceptible to interference.

[0067] Fig. 1 shows an embodiment in which the analog-to-digital converter (A / D) is arranged on the side of the circuit board 21 opposite the connector 19. This arrangement offers the advantage that there is ample space available on the side of the circuit board 21 opposite the connector 19, at a very short distance from the connector 19, for accommodating the analog-to-digital converter (A / D).

[0068] Another optional embodiment consists in the second component 17 being inserted into the passage 11 in such a way that it seals the passage 11 in a pressure-resistant manner.

[0069] This offers the advantage, particularly in conjunction with measuring instruments 100 whose measuring device 47 has at least one element in contact with a measuring medium during measuring operation, that even if the measuring device 47 is damaged or even destroyed, it is ensured that any process pressure prevailing on the side of the measuring medium cannot penetrate into the first chamber 7. Fig. 1 shows an embodiment in which the bushing 23 is connected to a housing area of ​​the housing 5 surrounding the passage 11 on all sides by a pressure-resistant connection 51, such as a weld shown by triangles in Fig. 1, either during or after the insertion of the second component 17 into the passage 11.

[0070] Another optional embodiment, also shown in Fig. 1, consists in the bushing 23 having a shoulder 53 projecting outwards on all sides, the end face of which, in the measuring instrument 100, faces the first chamber ? of the shoulder 5 against a stop surface 54 of the housing 5, which faces the second chamber 9 and surrounds the passage 11 on all sides. The shoulder 53, which can be used as an alternative or in addition to the previously described pressure-resistant connection 51, also offers the advantage of a correspondingly high pressure resistance of the closure of the passage 11 effected by the second component 17 against pressures acting on it through the second chamber 9.

[0071] Another optional embodiment, particularly advantageous with regard to the compressive strength of the closure of the passage 11 effected by the second component 17, consists in the passage 11 and, accordingly, also the plug connection 13 inserted therein having the smallest possible cross-sectional area, such as a cross-sectional area of ​​less than or equal to

[0072] 7 cm 2 , exhibits. This can be achieved, for example, by ensuring that passage 11 has a diameter of less than or equal to 3 cm.

[0073] Another optional feature is that the measuring device 100 is designed as a device that can be used in potentially explosive atmospheres.

[0074] In this case, the measuring device 100 is designed, for example, to meet the requirements for at least one type of explosion protection, such as intrinsic safety (Ex-i) and / or flameproof enclosure (Ex-d). In this respect, a housing area of ​​housing 5, for example, enclosing the first chamber, is designed as a flameproof housing to ensure that an explosion occurring in the first chamber cannot be transmitted to the outside. Alternatively or additionally, the first electronics 1 and / or the second electronics 3, for example, are each designed as intrinsically safe electronics that meet the aforementioned requirements for intrinsic safety.

[0075] Another optional embodiment, particularly advantageous with regard to fulfilling the intrinsic safety requirements, consists in filling an interior space surrounding the first electronics 1 in the first chamber with a potting compound. Potting the first electronics 1 allows components of the first electronics 1 to be arranged closer together while still meeting the intrinsic safety requirements. An optional embodiment of the connector 19, particularly advantageous with regard to the potting compound being still liquid during filling, consists in the connector 19 having a radially outwardly projecting shoulder 55 in a rear area adjacent to its front region 31. This shoulder, in conjunction with a seal 57 arranged in the housing 5 of the finished measuring device 100, such as an O-ring or a molded seal, provides a seal for the interior space surrounding the first electronics 1 in the first chamber.

[0076] In this embodiment, the first electronics 1 can be inserted directly into the first chamber, and the interior space surrounding the first electronics 1, formed in this case by the interior of the first chamber, can be filled with potting compound.

[0077] Alternatively, the first electronic component 1 can also be inserted into a cup-shaped insert, such as the insert described in German patent application DE102024119395.6 filed on July 9, 2024. In this case, the interior space surrounding the first electronic component 1, possibly filled with potting compound, corresponds to the interior space of the insert.

[0078] Fig. 1 shows an embodiment in which the first electronics 1 is arranged in the first chamber ? in a cup-shaped insert 59, the base of which has a through-opening 61 through which the plug 19 can be inserted into the socket 23 inserted into the passage 11. In this embodiment, the seal 57 is arranged such that it seals a gap existing between the shoulder 55 of the plug 19 and the base of the insert 59, which surrounds the through-opening 61 on all sides.

[0079] Measuring instruments 100 with insert 59 offer the advantage over alternatively usable embodiments without insert 59 that the insert 59 can be fitted with the first electronics 1 including the connector 19 before installation and potted if necessary, and can then be inserted as a module into the first chamber ?

[0080] A further advantage is that, in this embodiment, the seal 57 can be produced as a seal 57 connected to or formed as a component of the insert 59. In this case, the insert 59 and the seal 57 are manufactured, for example, in an injection molding process, such as a two-component injection molding process.

[0081] In the embodiment shown in Fig. 1, the seal 57 is designed in the manner described in German patent application DE102024119395.6, filed on July 9, 2024. In this respect, the seal 57 comprises a cylindrical section 57a ​​arranged in the passage opening 61, a sealing lip 57b projecting radially inwards at one end of the cylindrical section 57, and a sealing lip 57c projecting radially outwards at the other end of the cylindrical section 57a. The inwardly projecting sealing lip 57b is clamped between the base of the insert 59, which surrounds the passage opening 61 on all sides, and the shoulder 55 of the connector 19. The outwardly projecting sealing lip 57c is clamped between the bottom area of ​​the insert 59, which surrounds the passage opening 61 on all sides, and an inner surface of the housing 5, which surrounds the passage 11 on all sides.Accordingly, the inwardly projecting sealing lip 57b seals the gap between the shoulder 55 and the bottom of the insert 59 against the interior of the insert 59, and the outwardly projecting sealing lip 57c seals the gap against an interior space of the first chamber 7 surrounding the insert 59.

[0082] Reference symbol list:

[0083] Measuring device 35 Connection first electronics 37 Area second electronics 37' Area housing 39 Recess first chamber 41 Projection second chamber 43 Opening (second chamber) Passage 45 Opening (first chamber) Plug connection 47 Measuring device first component 49 Connection leads (2nd electronics) second component 50 Area plug 51 Pressure-resistant connection circuit board 53 Recess (socket) socket 54 Stop surface feedthrough 55 Recess (plug)

[0084] Connecting elements 57 Interior seal 59 Insert

[0085] Front area 61 Passage opening

[0086] Connection element

Claims

Patent claims 1. Measuring instrument (100) with a first electronics unit (1), a second electronics unit (3) and a housing (5) with a first chamber (7) for receiving the first electronics unit (1), a second chamber (9) and a passage (11) connecting the first chamber (7) with the second chamber (9), wherein: a detachable plug connection (13) is inserted into the passage (11), which comprises a first component (15) and a complementary second component (17), the first component (15) comprises a plug (19) of the first electronics unit (1), the second component (17) comprises a socket (23) in the interior (29) of which a front area (31) of the plug (19) is mechanically fitted, which has several areas (37, 37') arranged asymmetrically around the outside of the front area (31), each of which extends as a projection parallel to a longitudinal axis of the plug (19) or as a projection parallel to the longitudinal axis of the plug (19) extending indentation are formed,and the second component (17) comprises a feedthrough (25) made of an insulator adjacent to the interior (29) of the socket (23), through which electrically conductive connecting elements (27) extend, the first ends of which point into the interior (29) are connected by creating the plug connection (13) to terminal elements (33) of the first electronics (1) integrated in the plug (19) and complementary to the connecting elements (27), and the second ends of which opposite the first ends are connected to the second electronics (3).

2. Measuring instrument (100) according to claim 1, wherein the front area (31) has an asymmetric cross-sectional area and the interior (29) of the socket (23) complementary to the plug (19) has an asymmetric cross-sectional area corresponding to the cross-sectional area of ​​the front area (31), and / or the front area (31) of the plug (19) has three areas (37, 37') arranged on the outside around the plug (19).

3. Measuring instrument (100) according to claims 1 to 2, wherein each area (37) of the front area (31) of the connector (19) is formed as a projection, and / or each projection-formed area (37) of the front area (31) of the connector (19) has a cross-sectional area with an outer contour that is rounded on the outside or has a circular segment shape.

4. Measuring device (100) according to claims 1 to 3, wherein: the second component (17) is inserted into the passage (11) in such a way that it seals the passage (11) in a pressure-tight manner, and / or the socket (23) is connected to a housing area of ​​the housing (5) which surrounds the passage (11) on all sides by a pressure-resistant connection (51) or a pressure-resistant connection (51) designed as a weld.

5. Measuring instrument (100) according to claims 1 to 4, wherein the socket (23) has a shoulder (53) projecting on all sides on the outside, the end face of which in the measuring instrument (100) facing the first chamber (7) rests against a stop surface (54) of the housing (5) facing the second chamber (9).

6. Measuring instrument (100) according to claims 1 to 5, in which the first ends of the connecting elements (27) projecting into the interior (29) of the socket (23) are arranged recessed relative to an end face of the socket (23) facing the first chamber (7).

7. Measuring instrument (100) according to claims 1 to 6, comprising a measuring device (47) for the metrological acquisition of at least one measurand, wherein: the second electronics (3) is configured as measuring electronics connected to or integrated in the measuring device (47), and / or is configured to provide an analog measurement signal corresponding to the measurand acquired by means of the measuring device (47), and / or the first electronics (1) is configured to supply the second electronics (3) and / or the measuring device (47) with energy, to receive, digitize, process and / or evaluate measurement signals provided by the second electronics (3) via the connector (13), and / or to determine and provide measured values ​​of the measurand(s) based on the measurement signals.

8. Measuring device (100) according to claims 1 to 7, wherein: the second electronics (3) is configured to provide analog signals via the connector (13), and the first electronics (1) comprises an analog-to-digital converter (A / D) for digitizing the analog signals, which is arranged in an area of ​​the first electronics (3) immediately adjacent to the connector (19) and / or on a side of a circuit board (21) of the first electronics (3) opposite the connector (19).

9. Measuring device (100) according to claims 1 to 8, wherein the connector (19) has a shoulder (55) projecting outwards on all sides in a rear area adjacent to its front area (31), wherein: the shoulder (55) in conjunction with a seal (57) arranged in the housing (5) provides a seal for an interior space surrounding the first electronics (1) in the first chamber (7) or for an interior space surrounding the first electronics (1) in the first chamber (7) filled with a potting compound, and / or wherein the first electronics (1) is arranged in the first chamber (7) in a cup-shaped insert (59) or in a cup-shaped insert (59) filled with a potting compound, the insert (59) has a through-opening (61) through which the front area (31) of the plug (19) is inserted into the socket (23) inserted into the passage (11), and a gap existing between the shoulder (55) of the plug (19) and a base of the insert (59) surrounding the through-opening (61) on all sides is sealed by a seal (57).

10. Measuring instrument (100) according to claim 9, wherein the seal (57) is connected to the insert (59) or is formed as a component of the insert (59), and / or the seal (57) comprises a cylindrical area (57a) arranged in the passage opening (61), a sealing lip (57b) projecting radially inward at one end of the cylindrical area (57), and a sealing lip (57c) projecting radially outward at the other end of the cylindrical area (57), wherein the inwardly projecting sealing lip (57b) is clamped between a base area of ​​the insert (59) surrounding the passage opening (61) on all sides and the shoulder (55) of the plug (19), and the outwardly projecting sealing lip (57c) is clamped between the base area of ​​the insert (59) surrounding the passage opening (61) on all sides and an inner surface surrounding the passage (11) on all sides. of the housing (5) is clamped.

11. Measuring device (100) according to claims 1 to 10, wherein the passage (11) has a cross-sectional area of ​​less than or equal to 7 cm² 2is and / or has a diameter of less than or equal to 3 cm, the socket (23) is made of a metal or stainless steel, the connecting elements (27) are designed as contact pins and / or are made of a nickel-iron alloy, the feedthrough (25) is pressure-resistant in the socket (23) and / or is designed as a glass feedthrough, the plug (19) electrically connected to the first electronics (1) is mechanically attached to a circuit board (21) of the first electronics (1), the connecting elements (33) comprise sleeves, each lining a bore extending through the plug (19), the connecting elements (33) are connected or soldered at their ends to a connection (35) of the first electronics (1) arranged on the circuit board (21), the connecting elements (33) are made of a soft and / or spring-elastic conductive material, a metal and / or a copper-beryllium alloy,and / or the measuring device (100) is designed as a device suitable for use in potentially explosive atmospheres, 12. Measuring device (100) according to claims 1 to 11, wherein the second component (17) has seven connecting elements (27) or an odd number of connecting elements (27), all connecting elements (27) being arranged in the passage (25) distributed on the outside and / or in a circular pattern around a central area of ​​the passage (25), The distances between directly adjacent connecting elements (27) are equal and / or greater than or equal to an outer dimension or an outer diameter of the connecting elements (27), and / or the plug (19) has a planar surface (50) on its end face facing the socket (23), surrounded on the outside by the connecting elements (33).

13. Measuring instrument (100) according to claims 1 to 12, in which electrical connecting leads (49) of the second electronics (3) arranged in the second chamber (9) are each connected directly to the second end of one of the connecting elements (27) passing through the passage (25) by means of a joining, a joining produced by means of an automated joining process, and / or a joining designed as a welding, soldering or crimp connection.

14. Method for manufacturing a measuring instrument (100) according to claims 1 to 13, in which the second component (17) of the plug connection (13) is manufactured, the second electronics (3) is connected to the second ends of the connecting elements (27) of the second component (17), the second component (17) is inserted into the passage (I n) between the first chamber (7) and the second chamber (9), and the plug connection (13) is created by inserting the first electronics (1) equipped with the plug (19) into the first chamber (7) such that the front area (31) of the plug (19) is arranged in the interior (29) of the socket (23).

15. Method according to claim 14 for manufacturing a measuring device (100) according to claims 12 and 13, wherein the second electronics (3) is connected to the second ends of the connecting elements (27) of the second component (17) by means of a method or an automated method in which the feedthrough (25) is rotated stepwise and in each rotational position one of the connecting elements (27) is connected to the associated connecting line (49) by means of a joining tool comprising a tool component (W1) that can be attached from the outside to an outside of the respective joining point and a tool component (W2) that can be attached through a gap opposite the respective joining point to an inside of the joining point.

Images