Fill level measuring assembly

Abstract

Disclosed is a fill level measuring assembly (1) for measuring the fill level in a reservoir, wherein the fill level measuring assembly (1) can be arranged over a surface (2) of a material in the reservoir and comprises a sensor housing (4) that has a base plate (6) and defines an interior space (10), wherein a sensor assembly with evaluation electronics (12) and a sensor element (8) is arranged in the interior space (10) of the sensor housing (4), wherein the sensor element (8) is arranged in the base plate (6) and is designed to emit a measuring signal in the direction of the surface (2) and to receive a reflection signal reflected by the surface (2) in response to the measuring signal, wherein the sensor element (8) is set back in the base plate (6) in the direction of the interior space (10) of the sensor housing (4) in relation to the underside (14) of the base plate (6), which faces the surface (2) of the material.

Description

[0001] Description

[0002] Level measuring arrangement

[0003] The present invention relates to a level measuring arrangement for measuring the level in a reservoir according to the preamble of patent claim 1.

[0004] Reservoirs can be used to store a fluid or other substance and are usually connected to systems to transfer the contents of the reservoir to other devices or equipment. For example, the reservoir can be a lubricant reservoir in which oil or grease is stored, with the lubricant being delivered to lubrication systems for bearings or similar. In this case, it is often necessary to monitor the fill level of the reservoir. The fill level of the reservoir can be monitored by various monitoring devices, such as optical or acoustic sensors that measure a distance between the surface of the contents of the reservoir and the sensing element. The sensing elements are arranged so that they point towards the reservoir in order to perform their respective function. During service activities, maintenance operations or other movements within the reservoir, e.g.However, by stirring the contents, the reservoir's contents, such as grease or oil, can enter the area of ​​such a sensor element. There is therefore a risk that the sensor element will become heavily contaminated and the sensor function will no longer be guaranteed.

[0005] It is therefore an object of the present invention to provide a level measuring arrangement with a sensor element, in which the sensor element is protected from contamination. This object is achieved by a level measuring arrangement for measuring the level in a reservoir according to claim 1.

[0006] The level measuring arrangement for measuring the level in a reservoir can be arranged above a surface of a substance present in the reservoir. The reservoir can, for example, be a lubricant unit containing a lubricant, such as lubricating grease or oil, or can be any other type of reservoir, such as a fuel tank. In either case, the level measuring arrangement is arranged above a surface of the reservoir. The level measuring arrangement comprises a sensor housing with a base plate, wherein the sensor housing defines an interior space with the base plate, wherein a sensor arrangement with evaluation electronics and a sensor element is arranged in the interior of the sensor housing. The sensor element is arranged in the base plate and is configured to transmit a measurement signal toward the surface and to receive a reflection signal reflected from the surface in response to the measurement signal.The evaluation electronics can then use the time between the transmission of the measurement signal and the reception of the reflection signal for a transit time measurement in order to determine the fill level of the substance present in the reservoir.

[0007] To protect the sensor element in the base plate from contamination, unlike previous systems, the sensor element in the level measurement arrangement proposed here is set back from the underside of the base plate, which faces the surface of the material, toward the interior of the sensor housing. This means that the sensor element is not flush with the underside of the base plate, but is recessed relative to this underside, thus providing better protection against contamination.

[0008] According to one embodiment, the base plate has a cylindrical bore in which the sensor element is arranged. Such a cylindrical recess of the sensor element in the base plate has the advantage that, on the one hand, the sensor element can be protected from direct contact, in particular with grease in the reservoir, while at the same time the sensor element is easily accessible so that cleaning of the sensor element, if necessary, can be carried out easily and without special tools. According to another embodiment, the base plate has a conical bore, with the sensor element arranged in the tip of the conical bore and the opening of the cone facing towards the surface. Such a configuration is particularly advantageous when oil or other fluids are present in the reservoir, since, depending on the application, the fluid may splash into the area of ​​the sensor element.By countersinking the sensor element relative to the underside of the base plate, the sensor element is protected from direct contact with such a fluid, and on the other hand, splashes that reach the area of ​​the sensor element can run off and drip off in a defined manner on the funnel wall of the conical bore.

[0009] According to a further embodiment, the fill level measuring arrangement is arranged centrally above the reservoir. Such a central arrangement is advantageous because it ensures the transmission and reception of signals from the sensor element. If the fill level measuring arrangement is arranged too far toward the edge of the reservoir, it is possible that signals emitted by the sensor element are reflected not by the surface of the reservoir's contents, but by a wall surface of the reservoir. This would lead to an incorrect determination of the fill level.

[0010] According to a further embodiment, the base plate is an injection-molded element. Such an injection-molded element, particularly made of plastic, is advantageous because it enables simple and cost-effective production of the base plate and the recess formed in the base plate for the sensor element. The base plate can be easily inserted into the sensor housing and replaced as needed.

[0011] According to a further embodiment, the base plate is therefore replaceable and / or the base plate has a replaceable insert in which the sensor element is fastened. In this way, the fill level measuring arrangement can be used for various reservoirs and substances in the reservoir, since the base plate can be adapted accordingly to the contents of the reservoir, in particular with regard to the type and design of the recess in which the sensor element is arranged. Further advantages and advantageous embodiments are specified in the description, the drawings, and the claims. In particular, the combinations of features specified in the description and the drawings are purely exemplary, so that the features can also be present individually or in other combinations.

[0012] The invention will be described in more detail below with reference to exemplary embodiments illustrated in the drawings. The exemplary embodiments and the combinations shown in the exemplary embodiments are purely exemplary and are not intended to define the scope of the invention. This scope is defined solely by the appended claims.

[0013] They show:

[0014] Fig. 1 : a schematic sectional view of a level measuring arrangement;

[0015] Fig. 2: a perspective view of an embodiment of a base plate for the level measuring arrangement of Fig. 1;

[0016] Fig. 3 : a perspective view of another embodiment of a base plate for the level measuring arrangement of Fig. 1; and

[0017] Fig. 4: a perspective sectional view of the base plate of Fig. 3.

[0018] In the following, identical or functionally equivalent elements are identified by the same reference symbols.

[0019] Fig. 1 shows a fill level measuring arrangement 1 designed to measure the fill level of a substance in a reservoir. The fill level measuring arrangement 1 has a sensor housing 4 with a base plate 6, wherein the base plate 6 can be connected to the sensor housing 4 via fastening means 28. The sensor housing 4, with its base plate 6, defines an interior space 10 in which a sensor element 8 and evaluation electronics 12 are arranged. Furthermore, the sensor housing 4 comprises a connection 16 via which the fill level measuring system can be connected to external devices, such as computing devices, etc. The fill level measuring system can be connected to the reservoir (not shown) via fastening means 18. In order to measure the fill level 2, the sensor element 8 is designed to emit a signal that is reflected by a surface 2 of the contents of the reservoir and then received again by the sensor element 8.The sensor element 8 can be configured to transmit and / or receive the signal within a measuring lobe 20. The evaluation electronics 12 can then perform a time-of-flight measurement using the transmitted and reflected signal to determine a distance 22 between the sensor element 8 and the surface 2.

[0020] In a reservoir in which, for example, lubricating grease is stored, agitator blades may be provided to stir the contents of the reservoir. To protect the sensor element 8 from contamination by the contents of the reservoir, for example due to movement of the contents by such agitator blades, which splash the contents, such as oil, against the sensor element 8, the sensor element 8 is recessed in the base plate 6, as described below with reference to Figures 2-4.

[0021] Fig. 2 shows a first embodiment of a base plate 6 that can be connected to the sensor housing 4 shown in Fig. 1. Although the base plate 6 is shown in the figures as a square base plate 6 with bevels, the base plate can also be round or rectangular or in other shapes.

[0022] To protect the sensor element 8 from contamination, the base plate 6 shown here has a cylindrical bore 24. The sensor element 8 is arranged at the bottom of this cylindrical bore 24 and is thus set back from the underside 14 of the base plate. This places the sensor element 8 further away from the surface 2 of the reservoir contents, and the opening formed by the cylindrical bore 24 is small, reducing the likelihood of the reservoir contents reaching the sensor element 8.

[0023] The base plate 6 further has fastening openings 26 into which fastening means 28 can be inserted (see Fig. 1) in order to connect the base plate 6 to the sensor housing 4. The base plate 6 can be exchanged in order to enable adaptation of the level measuring arrangement 1 to different fluids or solids in the reservoir, i.e. in order to adapt the base plate and in particular the opening 24 in which the sensor element 8 is arranged, to the conditions of the reservoir. A further embodiment of the base plate 6 is shown in Figures 3 and 4. In this case, the base plate 6 has a conical bore 30 instead of a cylindrical bore 24, as shown in Fig. 2.Such a conical bore 30 is particularly suitable for fluids in the reservoir, since the conical design allows any liquid that reaches the sensor element 8 to be guided away from the sensor element 8 through the funnel design of the conical bore 30 and drain away. The sensor element 8 is arranged at the tip of the cone and is thus also set back from the underside 14 of the base plate 6.

[0024] The level measuring arrangement proposed here makes it possible to arrange a sensor element above a reservoir, whereby the sensor element is protected from contamination by the contents of the reservoir.

[0025] List of reference symbols

[0026] 1 level measuring system

[0027] 2 Surface

[0028] 4 sensor housings

[0029] 6 Base plate

[0030] 8 Sensor element

[0031] 10 interior element

[0032] 12 Evaluation electronics

[0033] 14 Bottom

[0034] 16 connection

[0035] 18 fasteners

[0036] 20 measuring cone

[0037] 22 Distance

[0038] 24 cylindrical bore

[0039] 26 mounting holes

[0040] 28 fasteners

[0041] 30 conical bore

Claims

P a t e n t a n s p r ü c h e Level measuring arrangement (1) for measuring the level in a reservoir, wherein the level measuring arrangement (1) can be arranged above a surface (2) of a substance present in the reservoir, and has a sensor housing (4) with a base plate (6) that defines an interior space (10), wherein a sensor arrangement with evaluation electronics (12) and a sensor element (8) is arranged in the interior space (10) of the sensor housing (4), wherein the sensor element (8) is arranged in the base plate (6) and is configured to send a measurement signal in the direction of the surface (2) and to receive a reflection signal reflected from the surface (2) in response to the measurement signal, characterized in that the sensor element (8) in the base plate (6) is set back in the direction of the interior space (10) of the sensor housing (4) with respect to the underside (14) of the base plate (6), which faces the surface (2) of the substance.Level measuring arrangement according to claim 1, wherein the base plate (6) has a cylindrical bore (24) in which the sensor element (8) is arranged. Level measuring arrangement according to claim 1, wherein the base plate has a conical bore (30), wherein the sensor element (8) is arranged in the apex of the conical bore (30) and the opening of the cone faces the surface (2). Level measuring arrangement according to any one of the preceding claims, wherein the level measuring arrangement (1) is arranged centrally above the reservoir. Level measuring arrangement according to any one of the preceding claims, wherein the base plate (6) is an injection-molded element. Level measuring arrangement according to any one of the preceding claims, wherein the base plate (6) is replaceable and / or wherein the base plate (6) has a replaceable insert in which the sensor element (8) is mounted.

Images