Housing assembly for a measuring device, and measuring device
The housing assembly addresses unreliable seals in field devices by using flange-like projections and angled surfaces to securely clamp the sealing element, ensuring a leak-proof and cost-effective solution for field devices in harsh environments.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- ENDRESS HAUSER FLOWTEC AG
- Filing Date
- 2025-12-02
- Publication Date
- 2026-06-25
AI Technical Summary
Existing field device housings in the food and pharmaceutical industries face issues with unreliable seals due to annular sealing elements slipping, leading to potential leaks, despite meeting hygiene standards and requiring regular high-pressure cleaning.
A housing assembly design featuring flange-like projections with integral sealing surfaces and a lateral projection supporting the sealing element, clamped between these surfaces, ensuring a secure seal through angled surfaces and preload elements to prevent slippage.
The design provides a reliable, leak-proof seal that withstands high-pressure cleaning, maintaining hygiene standards while reducing material and production costs by eliminating the need for thick walls and expensive materials.
Smart Images
Figure EP2025085192_25062026_PF_FP_ABST
Abstract
Description
[0001] Housing assembly for a measuring instrument and measuring instrument
[0002] This invention relates to a housing assembly for a measuring instrument for process and automation technology 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 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 and their components used in industrial applications generally need to be corrosion-resistant and chemically resistant. The use of field devices in the food industry entails further, specific requirements, including hygiene standards stipulating that all components of the field device that come into contact with process media, such as food, must be replaceable.
[0006] This applies in particular to the housings enclosed by most field devices, which serve, for example, to house an electronic circuit for processing the measurement signals and for communication with other devices.
[0007] Housings for field devices used in the food industry must be accessible for thorough internal cleaning and ideally have no undercuts where process media residues could accumulate. Additionally, the housing must remain leak-proof during extended use. This must be guaranteed even if it is regularly cleaned, for example, with a high-pressure steam cleaner commonly used in the food industry. Similar requirements apply in the pharmaceutical industry.
[0008] Housings often comprise components or parts of housing assemblies, which components or parts are shaped in such a way that they can be connected to each other without much effort, for example by inserting two or more parts into each other and then connecting them with a suitable fastener.
[0009] Housings are available on the market that consist of at least two parts, with one part, called the lid, screwed onto the other part, called the housing pot, via a multi-start thread. The lid and housing pot are typically cast parts made of aluminum or stainless steel. Such components are expensive. Due to the threads, these housings must have a wall thickness of at least approximately four millimeters to ensure sufficient mechanical stability. This wall thickness necessitates a minimum amount of material, and therefore a minimum weight and cost for the housings.
[0010] Document EP0837002A1 describes a housing for industrial applications, particularly for use in the food industry. The described housing comprises a housing pot with a removable lid. The lid surrounds the housing pot, forming a chamber in which an annular sealing element is located. This sealing element is radially clamped when the lid is closed. The described housing is robust, leak-proof, and cost-effective to manufacture.
[0011] However, the problem with the housing according to the prior art is that the annular sealing element can easily slip when the housing is closed, and therefore a reliable seal is not guaranteed. The object of the present invention is to provide a housing assembly that ensures a reliable seal between the housing components.
[0012] The housing assembly according to the invention for a measuring instrument for process and automation technology for detecting a measured quantity comprises: a sealing element; a container, wherein the container has a lateral projection with a cylindrical surface, the cylindrical surface being configured to serve as a radial support surface for the sealing element, the cylindrical surface being surrounded by the sealing element; a first housing part with a first flange-like projection, wherein the first flange-like projection has a first sealing surface; a second housing part with a second flange-like projection, wherein the second flange-like projection has a second sealing surface, wherein the first housing part is connected to the second housing part to form a housing chamber, the housing chamber enclosing the container, and wherein the sealing element is positioned by the lateral projection between the first sealing surface and the second sealing surface;wherein the housing chamber and the lateral projection have a vertical principal axis; wherein the lateral projection extends radially away from the vertical principal axis; wherein a compression of the first housing part and the second housing part clamps the sealing element between the first sealing surface and the second sealing surface, forming a sealing connection.
[0013] The advantage of the invention is that the sealing surfaces are mutually facing surfaces of the flange-like projections, wherein the flange-like projections are integrally formed with the housing parts, and wherein the flange-like projections are designed to function as a clamping element for the sealing element by means of connecting elements, in particular by means of screws. The sealing element can, for example, be an O-ring. A further advantage is that the lateral projection can also be flange-like in shape, wherein the projection does not act as a flange, but rather only as a lateral support surface for the sealing element.
[0014] In a further development of the housing assembly according to the invention, the container is held in the first housing part; a lower region of the container is surrounded by the first housing part; the lateral projection extends at least partially into a region surrounded by the first flange-like projection, in particular by the first sealing surface, and by the second flange-like projection, in particular by the second sealing surface.
[0015] The advantage of this design is that the container is held by at least the first housing part, thus defining the position of the lateral projection relative to the flange-like projections of the housing parts. This also positions the outer surface relative to the sealing surfaces, which in turn positions the sealing element surrounding the outer surface between the sealing surfaces in such a way that a sealing connection between the housing parts is possible.
[0016] In a further development of the housing assembly according to the invention, the first housing part and the container have complementary shapes to each other; the container is inserted into the first housing part.
[0017] In a further development of the housing assembly according to the invention, the container, the first housing part and the second housing part each have a rectangular basic shape.
[0018] In a further development of the housing assembly according to the invention, the first sealing surface has first connection points; the second sealing surface has second connection points; the first connection points and the second connection points are designed to be connected by a connecting means, in particular by a screw.
[0019] In a further development of the housing assembly according to the invention, the first sealing surface and the second sealing surface are arranged to be pressed together by means of a connection between the first connection points and the second connection points.
[0020] In a further development of the housing assembly according to the invention, the container is designed to accommodate an electronic component arrangement, in particular a measuring and operating circuit for the measuring device.
[0021] In a further development of the housing assembly according to the invention, the lateral surface has a first normal vector; the first sealing surface has a second normal vector; an angle enclosed by the first normal vector and by the second normal vector is greater than 90 degrees, in particular greater than 100 degrees, and preferably greater than 110 degrees.
[0022] One advantage of this design is that an angled or inclined surface exerts a force on the sealing element in a direction determined by the angle. In particular, an inclined surface generates a force that presses the sealing element against the first sealing surface.
[0023] In a further development of the housing assembly according to the invention, the lateral projection in a direction parallel to the vertical main axis is no more than 10 mm, in particular no more than 5 mm and preferably no more than 2.5 mm high.
[0024] In a further development of the housing assembly according to the invention, a basic form of the projection has several straight sides; the projection has at least one preload element at at least one corner; the preload element has a first surface; the projection has a second surface; the first surface has an angle to the second surface.
[0025] One advantage of this design is that the preload element holds the sealing element in position and, in particular, prevents it from slipping over a corner of the container. The preload element achieves this through an angle between the first and second surfaces, causing it to protrude beyond the second surface. The preload element is elastically connected to the container, allowing it to move when the first and second housing parts are joined, ensuring that the first surface is parallel to the second when the housing parts are assembled.
[0026] In a further development of the housing assembly according to the invention, the container has fastening elements, in particular locking lugs; the fastening elements are designed to hold a printed circuit board.
[0027] In a further development of the housing assembly according to the invention, the container has a contact pin arrangement; the contact pin arrangement is configured to be connected to a cable harness; the contact pin arrangement is configured to be connected to a printed circuit board.
[0028] The measuring device according to the invention for detecting a measured quantity of a medium comprises: a measuring tube; a sensor; a housing, wherein the housing comprises a housing assembly according to the invention; an electronics arrangement, wherein the electronics arrangement is arranged on a printed circuit board, the electronics arrangement comprising a measuring and operating circuit.
[0029] The invention is further explained using the following figures. It shows:
[0030] Fig. 1 shows an embodiment of the housing assembly according to the invention;
[0031] Fig. 2 shows a cross-section through one embodiment of the housing assembly;
[0032] Fig. 3 shows an enlarged representation of one embodiment of the housing assembly;
[0033] Fig. 4 shows a top view of one embodiment of the first housing part;
[0034] Fig. 5 shows a side view of one embodiment of the container;
[0035] Fig. 6 shows an enlarged representation of one design of the container;
[0036] Fig. 7 shows a schematic representation of an embodiment of a measuring device according to the invention.
[0037] The embodiment of the assembly according to the invention shown in Fig. 1 depicts the first housing part GT1 and the second housing part GT2, which are connected to form a housing chamber GK. The first housing part GT1 and the second housing part GT2 are arranged to one another via connections at the first flange-like projection FV1 and the second flange-like projection FV2. In this embodiment, the connections are made by screws at the corners of the rectangular base of the flange-like projections.
[0038] The cross-section through one embodiment of the housing assembly shown in Fig. 2 depicts the first housing part GT1 with the first flange-like projection FV1, which has a first sealing surface DF1, and a second housing part GT2 connected to the first housing part GT1 with a second flange-like projection FV2, which has a second flange-like projection FV2 with a second sealing surface DF2. In this embodiment, the first housing part GT1 partially surrounds the container B, which has a projection V at one end region with a sleeve M (not shown here). This projection extends radially outwards from a main axis A1 of the housing assembly and is surrounded by a sealing element DK.The sealing body DK extends into an area surrounded by the first flange-like projection FV1 and the second flange-like projection FV2, and is clamped by connecting the first housing part GT1 with the second housing part GT2 between the first sealing surface DF1 and the second sealing surface DF2.
[0039] The enlarged area shown in Fig. 3 of an embodiment of the housing assembly depicts the first flange-like projection FV1 with the first sealing surface DF1, which is integrally formed on the first housing part GT1 and has a second normal vector N2, as well as the second flange-like projection FV2 with the second sealing surface DF2, which is integrally formed on the second housing part GT2. The container B is surrounded by the first housing part GT1, and the container B has a projection V at an end region EB with a lateral surface M, which lateral surface M has a first normal vector N1. In this embodiment, the angle enclosed by the first normal vector N1 and the second normal vector N2 is greater than 90 degrees, so that the lateral surface M exerts a force on a sealing element DK surrounding the lateral surface M, which force presses the sealing element DK against the first sealing surface DF1.
[0040] The top view shown in Fig. 4 of an embodiment of the first housing part GT1 depicts the first sealing surface DF1, which has four first connection points VS1 and surrounds the container B. The first connection points VS1 are designed to be connected to the (not shown here) second connection points VS2 of the (not shown here) second housing part GT2. The outer surface M surrounding the container B is enclosed by the sealing element DK, which projects beyond the sealing surface DF1.
[0041] Figure 5 shows a side view of an embodiment of the container B with an end region EB, wherein the end region has a second surface 02 and a molded lateral projection V with a circumferential surface M, the lateral projection V having at least one straight side GS. The container B has several fastening elements BE and a contact pin arrangement KA, wherein the fastening elements BE are configured for attaching a printed circuit board LP, and wherein the contact pin arrangement KA is configured to be electrically connected to the printed circuit board LP on one side and to a cable harness by means of contact pins on the other side.The contact pin arrangement enables the transmission of electrical signals to and from the circuit board, for example for processing measurement signals by a measurement and operating circuit arranged on the circuit board, and / or supplying a measuring sensor with electrical current, and / or controlling a measuring sensor.
[0042] The enlarged view in Fig. 6 shows an embodiment of container B with a lateral projection V formed at the end region EB, having a lateral surface M. Container B has several straight sides GS, with each pair of straight sides GS adjoining a prestressing element VE, which has a first surface. In this embodiment, container B has a rectangular base and a prestressing element VE at each corner. The prestressing elements VE have a first surface 01, which forms an angle with a second surface of container B.
[0043] Figure 7 shows a schematic representation of an embodiment of a measuring device according to the invention. The medium ME is guided in a measuring tube MR and is in contact with a sensor MA arranged on the measuring tube. The sensor MA is configured to detect a measured quantity of the medium ME and to transmit a measurement signal to the measuring and operating circuit arranged on an electronic assembly EA. The electronic assembly EA is arranged in a housing G, the housing G comprising a housing assembly according to the invention. (List of reference numerals)
[0044] DK sealing body
[0045] B Container
[0046] V lateral protrusion
[0047] M surface area
[0048] GT1 first housing part
[0049] FV1's first flange-like advantage
[0050] DF1 first sealing surface
[0051] GT2 second housing part
[0052] FV2 second flange-type advantage
[0053] DF2 second sealing surface
[0054] GK housing chamber
[0055] A1 vertical principal axis
[0056] UB lower area
[0057] VS1 first connection points
[0058] VS2 second connection points
[0059] EA Electronic Component Arrangement
[0060] N1 first normal vector
[0061] N2 second normal vector
[0062] GS straight sides
[0063] VE prestressing element
[0064] 01 first surface
[0065] 02 second surface
[0066] BE Fasteners
[0067] LP circuit board
[0068] KA contact pin arrangement
[0069] ME Medium
[0070] MR measuring tube
[0071] MA sensor
[0072] G Housing
[0073] MB measuring and operating circuit
Claims
Patent claims 1. Housing assembly for a measuring instrument for process and automation technology for recording a measured quantity, comprising: - a sealing element (DK); - a container (B), o wherein the container (B) has a lateral projection (V) with a lateral surface (M), o wherein the lateral surface (M) is configured to serve as a radial support surface for the sealing body (DK), o wherein the lateral surface (M) is surrounded by the sealing body (DK); - a first housing part (GT 1 ) with a first flange-like projection (FV1 ), wherein the first flange-like projection (FV1 ) has a first sealing surface (DF1 ); - a second housing part (GT2) with a second flange-like projection (FV2), wherein the second flange-like projection (FV2) has a second sealing surface (DF2); o wherein the first housing part (GT1 ) is connected to the second housing part (GT2) to form a housing chamber (GK), o wherein the housing chamber (GK) encloses the container (B), o wherein the sealing element (DK) is positioned by the lateral projection (V) between the first sealing surface (DF1 ) and the second sealing surface (DF2); - wherein the housing chamber (GK) and the lateral projection (V) have a vertical principal axis (A1 ); - wherein the lateral projection (V) extends radially away from the vertical principal axis (A1 ); - wherein a compression of the first housing part (GT1 ) and the second housing part (GT2) clamps the sealing element between the first sealing surface (DF1 ) and the second sealing surface (DF2) forming a sealing connection.
2. Housing assembly according to claim 1 , - wherein the container (B) is held in the first housing part (GT1); - wherein a lower area (UB) of the container (B) is surrounded by the first housing part (GT1); - wherein the lateral projection (V) extends at least partially into an area surrounded by the first flange-like projection (FV1), in particular by the first sealing surface (DF1), and by the second flange-like projection (FV2), in particular by the second sealing surface (DF2).
3. Housing assembly according to one of claims 1 or 2, - wherein the first housing part (GT1) and the container (B) have complementary shapes to each other; - wherein the container (B) is inserted into the first housing part (GT1 ).
4. Housing assembly according to one of claims 1 to 3, - wherein the container (B), the first housing part (GT1) and the second housing part (GT2) each have a basic shape with a simple, in particular rectangular or circular, geometry.
5. Housing assembly according to one of claims 1 to 4, - wherein the first sealing surface (DF1) has first connection points (VS1); - wherein the second sealing surface (DF2) has second connection points (VS2); - wherein the first connection points (VS1) and the second connection points (VS2) are arranged to be connected, in particular by a connecting means and preferably by a screw.
6. Housing assembly according to claim 5, - wherein the first sealing surface (DF1 ) and the second sealing surface (DF2) are arranged to be pressed together by means of a connection of the first connection points (VS1 ) and the second connection points (VS2).
7. Housing assembly according to one of claims 1 to 6, - wherein the container (B) is designed to accommodate an electronic component arrangement (EA), in particular a measuring and operating circuit for the measuring instrument.
8. Housing assembly according to claims 1 to 8, - where the lateral surface (M) has a first normal vector (N1 ); - wherein the first sealing surface (DF1 ) has a second normal vector (N2); - wherein an angle enclosed by the first normal vector (N1 ) and by the second normal vector (N2) is greater than 90 degrees, in particular greater than 100 degrees, and preferably greater than 110 degrees.
9. Housing assembly according to one of claims 8 or 9, - wherein the lateral projection (V) in a direction parallel to the vertical principal axis (A1) is not more than 10 mm, in particular not more than 5 mm and preferably not more than 2.5 mm high.
10. Housing assembly according to one of claims 8 to 10, - wherein a basic form of the projection (V) has several straight sides (GS); - wherein the projection (V) has at least one pre-tensioning element (VE) at at least one corner; - wherein the prestressing element (VE) has a first surface (01 ); - wherein the projection (V) has a second surface (O2); - where the first surface (01 ) has an angle to the second surface (O2).
11. Housing assembly according to one of claims 1 to 11 , - wherein the container (B) has fastening elements (BE), in particular locking lugs; - wherein the fastening elements (BE) are designed to hold a printed circuit board (LP).
12. Housing assembly according to one of claims 1 to 12, - wherein the container (B) has a contact pin arrangement (KA); - wherein the contact pin arrangement (CA) is configured to be connected to a wiring harness; - wherein the contact pin arrangement is designed to be connected to a printed circuit board (PCB).
13. Measuring device for detecting a measured quantity of a medium (ME), comprising: - A measuring tube (MR); - A sensor (MA); - A housing (G), wherein the housing (G) comprises a housing assembly according to any one of claims 1 to 13; - an electronic assembly (EA), o wherein the electronic assembly (EA) is arranged on a printed circuit board (PCB), o wherein the electronic assembly (EA) comprises a measurement and operating circuit (MC).