Housing assembly for a measuring device, and measuring device

Abstract

A housing assembly for a measuring device comprises a housing part (GT) having a planar viewing pane (SS); a connecting element (VE) which is arranged on the housing part (GT); a printed circuit board (LP) which is arranged on the connecting element (VE) and has a surface which is substantially parallel to the viewing pane (SS); wherein a first distance (A1) is defined between the viewing pane (SS) and the surface of the printed circuit board (LP); an HMI module (HMI) having display and operating functions and a planar module surface (MOF) facing the viewing pane (SS) and parallel thereto, the HMI module (HMI) being mechanically connected to the printed circuit board (LP), wherein a second distance (A2) is defined between the module surface (MOF) and the printed circuit board (LP); wherein a distance (A) between the viewing pane (SS) and the module surface (MOF) is defined by the first distance (A1) and the second distance (A2), wherein an intermediate space which is free of mechanical components is formed between the viewing pane (SS) and the module surface (MOF).

Description

[0001] Housing assembly for a measuring instrument and measuring instrument

[0002] The invention relates to a housing assembly with a human-machine interface (HMI) module for a measuring instrument, and a measuring instrument with a housing assembly according to the invention.

[0003] In automation technology, particularly in process automation, field devices are frequently used to detect and / or control process variables. Sensors, such as those integrated into level gauges, flow meters, pressure and temperature gauges, pH / ORP meters, conductivity meters, etc., are used to detect process variables, measuring levels, flow rates, pressure, temperature, pH, ORP, and conductivity. Actuators, such as valves or pumps, are used to control process variables, changing the flow rate of a liquid in a pipe section or the fill level in a container. In principle, field devices are all those devices used close to the process that provide or process process-relevant information.

[0004] In the context of the invention, field devices also include remote I / Os, radio adapters, and electronic components in general that are arranged at the field level. A large number of such field devices are manufactured and distributed by Endress+Hauser.

[0005] Field devices may be located in corrosive environments or exposed to the risk of fire or vibration, and due to explosion hazards, they must be explosion-proof; that is, they generally need to be able to withstand the operating conditions. It is often desirable to be able to configure field devices on-site without having to open an enclosure, as these can be difficult to remove and reattach, and removing covers exposes the internal components of the field devices to the environment. For this purpose, field devices with a display arrangement have long been used, comprising a human-machine interface (HMI) module with a digital display and a contact structure that responds to touch or proximity.Document W02012036804A2 describes a display arrangement comprising a transparent cover, a display panel with a contact structure (an HMI module), and an electronic circuit board cover, all mechanically connected by a connecting element that allows axial displacement and rotation. This document describes a clamping element that brings the contact structure of the display panel into contact with the transparent cover, pressing the two together. The contact structure contains a display circuit for a digital display and a touch circuit for activation through the transparent cover. The described display arrangement is robust and allows manipulation of the field device via a touch display without requiring the cover to be opened.

[0006] The problem lies in the fact that the mechanical connection between the HMI module and / or the circuit board on one side, and the display panel on the other, is achieved through components that conduct vibrations and heat into the housing and also occupy a portion of the available space. This connection can generate internal forces that may cause malfunctions in the electronic components and / or compromise the seal of the display panel. Furthermore, a mechanical connection can leak if the necessary components are damaged, making a connection with multiple components disadvantageous and unreliable.

[0007] The invention is based on the objective of providing a housing assembly that reliably insulates the electronic components inside the housing from the outside.

[0008] The invention solves the problem with a housing assembly according to claim 1.

[0009] The housing assembly according to the invention for a measuring instrument comprises a housing part with a planar viewing window, a connecting element wherein the connecting element is arranged on the housing part, a printed circuit board wherein the printed circuit board is arranged on the connecting element, wherein the printed circuit board has a surface substantially parallel to the viewing window, wherein a first distance between the viewing window and the surface of the printed circuit board is defined, an HMI module which has display and operating functions, wherein the HMI module has a planar module surface which faces the viewing window and is substantially parallel to the viewing window, wherein the HMI module is mechanically connected to the printed circuit board, wherein a second distance between the module surface and the printed circuit board is defined, wherein a distance between the viewing window and the module surface is defined by the first distance and the second distance.wherein a gap is formed between the viewing window and the module surface, which is free of mechanical components.

[0010] The invention has the advantage that the surface of the HMI module is separated from the viewing window by an air gap, i.e., a space free of mechanical elements. This separation of (or the air gap between) the HMI module and the viewing window insulates the HMI module and other electronic components from vibrations and heat from outside the housing. Furthermore, the positioning of the electronic components and the HMI module by the connecting element requires less space than mechanical mountings. Another advantage is that the connection between the connecting element, the viewing window, and the housing part is sealed by means of a sealing element (for example, an O-ring), which is clamped between the viewing window and the housing part.Furthermore, the advantage lies in the fact that the distance between a surface of the HMI module and a planar surface of the viewing window is adjustable via the dimensions of the connecting element. Another advantage is that the sum of all manufacturing and component tolerances results in an overall tolerance of 1 mm for the distance between a surface of the HMI module and a planar surface of the viewing window. Additionally, the connecting element positions the HMI module on the circuit board, eliminating the need for any further (mechanical) positioning elements. Finally, the circuit board is supported solely by the connecting element, thus eliminating the need for any additional (mechanical) support elements.

[0011] In a further development of the housing assembly according to the invention, the HMI module has a raised section with a first height, wherein the HMI module has a display element with a second height. A further advantage is that the raised section (also referred to as a display riser) is made of polycarbonate and the raised section determines the distance between a surface of the HMI module and a planar surface of the viewing window.

[0012] In a further development of the housing assembly according to the invention, the display element is configured to visually signal changing information. The advantage is that the display element includes a display which is configured to show information relating to the measuring instrument, for example, dynamic measured values, status indicators, error codes, QR codes, and operating instructions.

[0013] In a further development of the housing assembly according to the invention, the display element is configured to detect the position of a dielectric change on an outer side of the viewing window.

[0014] The HMI module offers the advantage of a contact structure arranged on its surface and designed to respond to capacitive changes caused by touching the viewing window. This allows the electronic components on the circuit board, and in particular the measuring and operating circuitry of the instrument, to be operated by touching the viewing window. Furthermore, operating the HMI module via the contact structure by touching the viewing window enables control of the instrument's functions. An additional advantage is that the distance between the HMI module's contact structure can be adjusted to respond to capacitive changes in the viewing window. This requires, in particular, that the distance be less than the maximum distance.

[0015] In a further development of the housing assembly according to the invention, a maximum distance is achieved by the fact that the display element can detect a dielectric change on an outer surface of the viewing window for any distance smaller than the maximum distance. In a further development of the housing assembly according to the invention, the maximum distance is no more than 5 mm, in particular no more than 3 mm, and preferably no more than 2.0 mm.

[0016] In a further development of the housing assembly according to the invention, the distance is at least in some areas no less than one, in particular one half, and preferably one tenth of a tolerance; wherein the tolerance is no more than 2 mm, in particular no more than 1 mm, and preferably no more than 0.5 mm.

[0017] In a further development of the housing assembly according to the invention, the second distance is given by the first height and the second height.

[0018] In a further development of the housing assembly according to the invention, the display element comprises a grid made of conductive materials.

[0019] In a further development of the housing assembly according to the invention, the connecting element has first connection points, wherein the first connection points are designed to be connected to the housing part.

[0020] The advantage is that the connecting element can be connected to the housing part, in particular by means of screws and preferably via the first connection points.

[0021] In a further development of the housing assembly according to the invention, the connecting element has second connection points, wherein the second connection points are designed to be connected to the printed circuit board.

[0022] The advantage is that the circuit board can be connected to the connecting element by means of screws at the connection points, especially the second connection point.

[0023] In a further development of the housing assembly according to the invention, the connecting element is configured to position the viewing window, wherein a sealing connection between the connecting element, the housing part and the viewing window is provided by connecting the connecting element to the housing part. FL1408-WQ 6

[0024] In a further development of the housing assembly according to the invention, the sealing connection of the viewing window and connecting element comprises a sealing body.

[0025] In a further development of the housing assembly according to the invention, the connecting element is designed to position the HM I module on the circuit board.

[0026] The measuring device according to the invention comprises a housing including a housing assembly, a measuring and operating circuit, a sensor and a container designed to carry a medium.

[0027] The advantage of the measuring device according to the invention is that it can be used in hotter and more vibration-prone process environments than comparable measuring devices according to the prior art.

[0028] The invention is described by the following figures. They show:

[0029] Fig. 1 shows a cross-section through an embodiment of the housing assembly according to the invention;

[0030] Fig. 2 shows a cross-section of a design of part of the housing assembly;

[0031] Fig. 3 shows a top view of one embodiment of the connecting element;

[0032] Fig. 4 shows a top view of one embodiment of the HMI module extension;

[0033] Fig. 5 shows a schematic cross-section through an embodiment of the measuring device according to the invention.

[0034] Fig. 1 shows a schematic cross-section through an embodiment of the housing assembly according to the invention, comprising the connecting element VE, which is connected to the housing part GT and, in particular, to the planar viewing window SS arranged in the housing part GT, forming a sealing connection by means of first connection points (not shown here). In this specific embodiment, the connection between the connecting element VE and the housing part GT is provided by means of screws. The connecting element has second connection points AS2 at a lower end region, which are connected to the printed circuit board LP. In this specific embodiment, the printed circuit board LP is connected to the second connection points AS2 by means of screws.By connecting the connecting element VE to the housing part GT and the printed circuit board LP, a planar surface of the printed circuit board LP facing the viewing window SS has a defined first distance to a planar surface of the viewing window SS facing the printed circuit board LP. An HMI module HMI is arranged on the printed circuit board LP. In this embodiment, the HMI module HMI has a display element AE with a second height H2 and a raised section E with a first height H1, wherein a module surface MOF has a second distance A2 from the printed circuit board LP, the second distance A2 being defined by the first height H1 and the second height H2. A distance A between the module surface MOF and the surface of the viewing window SS facing the printed circuit board LP is given by a function of the first distance A1 and the second distance A2.In this specific example, the manufacturing tolerances of the individual components of the HMI module HMI are less than 1 mm, with a structurally determined tolerance range of the distance A being 1 mm.

[0035] Fig. 2 shows a cross-section of an embodiment of a part of the housing assembly, comprising the connecting element VE, the viewing window SS, the printed circuit board LP, and a sealing element DK. The connecting element VE is pressed against the viewing window SS, which in turn is pressed against the sealing element DK, which is pressed against the housing part GT (not shown). This creates a sealing connection between the viewing window SS, the sealing element DK, and the housing part GT. After pressing, the connecting element VE is attached to the housing part GT (not shown) by means of the first connection points AS1 located at an upper end. In this embodiment, the printed circuit board LP is connected to the connecting element VE at a lower end via the second connection points AS2 using screws. The raised section E of the HMI module HMI is located on the printed circuit board LP and is positioned by the connecting element VE.The indicator element AE is arranged on the raised section E. In this embodiment, it is configured to detect a capacitive change generated by touching the viewing window SS. In this embodiment, the detection of a capacitive change is achieved by a grid of conductive materials. Figure 3 shows a top view of a frame-shaped embodiment of the connecting element VE according to the invention. It shows the first connection points AS1 and the second connection points AS2 molded into the element in this embodiment. These connection points are designed to be connected to the housing part GT (not shown here) and the printed circuit board LP by means of screws. This embodiment of the connecting element VE has an upper frame designed to encompass a planar viewing window SS and, by means of a sealing element DK, to press the viewing window SS against the housing part GT, forming a sealing connection.

[0036] Fig. 4 shows a top view of an embodiment of the raised section E of the HMI module HMI, with an upper side OS, the upper side OS being configured to mount the display element AE (not shown in this figure). Furthermore, this specific embodiment of the raised section E has clamping elements designated as collars K, which collar K is configured to attach the display element AE to the raised section E. The collar K is also configured to dampen vibrations of the display element AE, where these vibrations are parallel to a surface of the upper side OS. In this embodiment, the raised section E is attached to the printed circuit board LP (not shown in this figure) by means of snap-fit ​​tabs RN.

[0037] Fig. 5 shows a schematic cross-section through an embodiment of the measuring device according to the invention, which has a sensor MA configured to detect at least one measured quantity of a medium M contained in a container B. The measuring device has a housing G, which comprises a housing assembly according to the invention, wherein a measuring and operating circuit MB is arranged on the electronic components within the housing G. In this specific embodiment, the measuring and operating circuit MB is at least partially arranged on the printed circuit board LP of the assembly according to the invention and can be operated by touching the planar viewing window SS, in particular by a capacitive change on an outer surface of the viewing window SS which is detected by the HMI module HMI. List of reference numerals

[0038] GT housing part

[0039] SS viewing window

[0040] VE connecting element

[0041] LP circuit board

[0042] A1 first distance

[0043] HMI HMI module

[0044] MOF module surface

[0045] A2 second distance

[0046] A distance

[0047] DM sealant

[0048] E increase

[0049] H1 first height

[0050] AE Display Element

[0051] H2 second height

[0052] AS1 first interchanges

[0053] AS2 second interchange

[0054] DK sealing body

[0055] K collar

[0056] OS Top side

[0057] G Housing

[0058] MB measuring and operating circuit

[0059] MA sensor

[0060] B Container

[0061] M Medium

Claims

Patent claims 1. Housing assembly for a measuring instrument, comprising: - A housing part (GT) with a planar viewing window (SS); - a connecting element (VE); o wherein the connecting element (VE) is arranged on the housing part (GT); - a printed circuit board (PCB), o wherein the PCB is arranged on the connecting element (FE), o - an HMI module (HMI) which has display and operating functions, o wherein the HMI module (HMI) has a planar module surface (MOF) which faces the viewing window (SS) and is substantially parallel to the viewing window (SS), o wherein the HMI module (HMI) is mechanically connected to the printed circuit board (PCB), - wherein a gap (A) is formed between the viewing window (SS) and the module surface (MOF), - wherein a space is formed between the viewing window (SS) and the module surface (MOF) which is free of mechanical components.

2. Housing assembly according to claim 1 , - wherein the printed circuit board (PCB) has a surface that is substantially parallel to the viewing window (BS); - wherein a first distance (A1 ) is defined between the viewing window (SS) and the surface of the printed circuit board (LP); - where a second distance (A2) is defined between the module surface (MOF) and the printed circuit board (PCB); - where a distance (A) between viewing window (SS) and module surface (MOF) is defined by the first distance (A1) and the second distance (A2).

3. Housing assembly according to claim 1 or 2, - wherein the HMI module (HMI) has a rise (E) with a first height (H1); - wherein the HMI module (HMI) has a display element (AE) with a second height (H2).

4. Housing assembly according to claim 3, - wherein the display element (AE) is set up to visually signal changing information.

5. Housing assembly according to claim 3 or 4, - wherein the display element (AE) is configured to detect the position of a dielectric change on an outside of the viewing window (SS).

6. Housing assembly according to claim 5, - where a maximum distance is given by the fact that the display element (AE) can detect a dielectric change on an outside of the viewing window (SS) for any distance (A) that is less than the maximum distance.

7. Housing assembly according to claim 6, - wherein the maximum distance is not more than 5 mm, in particular not more than 3 mm, and preferably not more than 2.0 mm.

8. Housing assembly according to one of claims 1 to 7, - wherein the distance (A) is at least in some areas not less than a simple, in particular half, and preferably one tenth of a tolerance; - wherein the tolerance is not more than 2 mm, in particular not more than 1 mm, and preferably not more than 0.5 mm.

9. Housing assembly according to one of claims 3 to 8, - where the second distance (A2) is given by the first height (H1) and the second height (H2).

10. Housing assembly according to one of claims 3 to 9, - wherein the display element (AE) comprises a grid of conductive materials.

11. Housing assembly according to one of claims 1 to 10, - wherein the connecting element (VE) has first connection points (AS1 ); - wherein the first connection points (AS1) are set up to be connected to the housing part (GT).

12. Housing assembly according to one of claims 1 to 11 , - wherein the connecting element (VE) has second connection points (AS2); - the second connection points (AS2) are designed to be connected to the printed circuit board (PCB).

13. Housing assembly according to one of claims 1 to 12, - wherein the connecting element (VE) is designed to position the viewing window (SS); - wherein a sealing connection, in particular comprising a sealing element (DK), is provided between the housing part (GT) and the viewing window (SS) by means of a connection of the connecting element (VE) with the housing part (GT).

14. Housing assembly according to one of claims 1 to 13, - wherein the connecting element (VE) is designed to position the HMI module (HMI) on the printed circuit board (LP).

15. Measuring device, including: - A housing (G) comprising a housing assembly according to any one of claims 1 to 14; - A measuring and operating circuit (MB); - A sensor (MA) - A container (B) designed to hold a medium (M).

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