DE102019201400A1 - Switching point extension for limit switches - Google Patents

Abstract

The invention relates to a switching point extension for positioning a measuring device for level measurement, for limit level determination and / or for pressure measurement, for example by means of an impedance limit switch, a vibration limit switch, a pressure sensor and / or a guided radar (time-domain reflectometer, TDR). The switching point extension (30, 40) has a large number of hollow tubular elements (33, 43), a connecting element (34, 44) which is set up to connect two tubular elements (33, 43), and a line arrangement (47, 48), which is set up for connection to a measuring device (10) when the measuring device (10) is attached to a first end (31, 41) of the switching point extension (30, 40), with the switching point extension (30, 40) being included set up to position the measuring device (10), which is arranged at a first end (31, 41) of the switching point extension (30, 40), at a predefined distance from a second end (32, 42) of the switching point extension (30, 40) .

Description

Field of the Invention

The invention relates to a switching point extension for positioning a measuring device for level measurement or for determining the level, for example by means of an impedance limit switch, a vibration limit switch, a pressure sensor and / or a guided radar (time domain reflectometer, TDR). The invention also relates to a level measuring device, a point level sensor, a method and uses.

background

Various types of measuring devices are used for level measurement or for determining the level, for example in a container, for example impedance limit switches, vibration limit switches, pressure sensors and / or guided radar sensors. These measuring devices are used in particular to measure a certain level of a filling material, e.g. in the container to indicate whether a predefined upper, lower or other limit of the level in the container has been reached. The container can be a vessel or measuring tank of any shape. The container can also be a channel, for example a stream or river bed.

In order to be able to position such a measuring device exactly, an individually adapted measuring device must be used for each application in the process industry, for which the “length” of the switching point or the distance between the fastening of the measuring device and the position of the switching point must be determined in each individual case. be used. This not only results in higher costs for the production of the customized measuring device, but in many cases also additional costs for warehousing. Furthermore, from a certain length of the measuring device it can be difficult to position the measuring device.

Summary of the invention

It is an object of the invention to provide a device for positioning a measuring device for level measurement, for level determination or for pressure measurement

This object is achieved by the subject matter of the independent claims. Further developments of the invention result from the subclaims and the following description.

A first aspect of the invention relates to a switching point extension for positioning a measuring device for level measurement, for level determination and / or for pressure measurement. The switching point extension has a multiplicity of hollow tubular elements and a connecting element which is set up to connect two tubular elements each. Furthermore, the switching point extension has a line arrangement which is set up for connection to a measuring device if the measuring device is attached to a first end of the switching point extension. The switching point extension is set up to position the measuring device, when it is attached to the first end of the switching point extension, at a predefined distance from a second end of the switching point extension.

The measuring device can, for example, be a vibration limit switch which e.g. as a limit switch, the minimum, maximum or other limit level of granulated and coarse-grained, powdery and fine-grained bulk goods is detected. The measuring device can also be a TDR sensor (TDR: Time Domain Reflectometer) for continuous level and interface measurement of liquids. The measuring device can also be set up for pressure measurement. Further examples of such devices are an impedance limit switch, a level measuring device with a high frequency front end, ultrasonic front end or laser front end or a pressure measuring device.

The measuring device can be arranged at a first end of the switching point extension. The measuring device can be positioned, for example, at the measuring location. For this purpose, the components can be delivered individually to the measuring location and only assembled there for and / or during positioning. Because each one of the plurality of hollow tubular elements is shorter than the entire switching point extension, the manufacture, storage and / or positioning can be made easier and / or less expensive. The hollow tubular elements can e.g. be cylindrical, oval, polygonal, or have a different cross-sectional shape. Depending on the embodiment of the switching point extension, the hollow inner part of the tubular elements can be advantageous because this makes the switching point extension easier, because further components of the switching point extension, e.g. mechanical or electrical cables can be arranged or for embodiments that are designed telescopic.

The at least one connecting element, which is set up to connect two tubular elements each, can - depending on the embodiment of the switching point extension - be arranged on the hollow tubular elements using different methods. The connecting element can, for example, be glued, soldered, welded, shrunk, riveted, screwed to each of the tubular elements, and / or a combination of these methods. The connecting element can be releasably or non-releasably connected to one of the tubular elements. Predefined requirements for the tightness of the switching point extension can be specified, so that the pipe elements, the connecting element or the connecting elements and the type of assembly must be able to meet these specifications. This can include special connection techniques, for example a maximum permissible temperature load on the connection point, and / or certain tests and / or certifications. The predefined distance from a second end can be known before positioning the measuring device. However, it is also possible to determine the distance only during the positioning. In particular, a specially specified connecting element can be designed such that repositioning, for example multiple repositioning, of the measuring device is possible. Repositioning can also take place, for example, as part of maintenance.

This switching point extension can make the positioning of the measuring device easier, cheaper, more flexible and / or more precise. The switching point extension can e.g. have a total length of 6 meters and more. The positioning of the measuring device can be easier, especially in confined spaces. The need for auxiliary devices can be reduced, for example a crane can no longer be required or a smaller crane can be sufficient for the positioning. The costs for storage and / or transportation can also be reduced because e.g. only a selection of standard lengths of pipe elements - and possibly only a few, shorter, special lengths - of the pipe elements must be kept in stock.

In one embodiment, the connecting element comprises a sealing element. This can simplify the assembly and / or contribute to a higher tightness of the switching point extension.

In one embodiment, the line arrangement has an expandable cable with a plug. The stretchable cable and the plug are set up to establish an electrical connection between the measuring device and evaluation electronics attached to the second end. The plug can be arranged in the region of the second end of the switching point extension. The stretchable cable can be designed, for example, as a spiral cable. The stretchable cable can be firmly connected to the measuring device, for example in order to prevent a lack of tightness at the entry point of the cable.

In one embodiment, the expandable cable is routed inside the plurality of hollow tubular elements. This can simplify the handling of the cable and / or protect the cable against external influences.

In one embodiment, the tubular elements are designed such that the inner diameter of a first tubular element is larger than the outer diameter of a second tubular element. The first and the second tubular element can be designed coaxially. In this embodiment, the switching point extension can be made telescopic. The connection of the telescopic pipe elements can e.g. be realized by one of the connection methods mentioned above, but also by tilting, cascaded screwing and / or a type of bayonet lock.

In one embodiment, the switching point extension has a length of more than 3 meters, for example more than 5 meters. The pipe elements or individual segments are shorter than 2 meters, for example shorter than 1 meter.

In one embodiment, the sealing element has a clamping element. The clamping element can be a single connection method or can also be combined with other connection methods.

In one embodiment, the tubular elements have an essentially identical outer diameter. In this embodiment, the switching point extension can be designed to be segmentable.

In one embodiment, the connecting element has an internal thread, which is set up to engage in an external thread of the tubular elements. With this e.g. the pipe elements are screwed to the connecting elements. A seal can be arranged between the tubular elements and / or in the connecting elements.

In one embodiment, the switching point extension is designed to be telescopic. The connection can be carried out, for example, by rotating the pipe elements and the connection element and / or by another of the connection methods mentioned above.

In one embodiment, the switching point extension is designed to be segmentable. The connection can include an engagement of the external thread of the tubular elements in an internal thread of the connection element and / or another of the connection methods mentioned above.

In one embodiment, the telescopic and the segmentable components of the switching point extension can be combined.

Another aspect of the invention relates to a level measuring device, a point level sensor and / or a pressure sensor, which has a switching point extension as described above or below.

In one embodiment, the level measuring device or the level sensor is designed as a guided radar, TDR, or as a vibration level switch or as a pressure sensor.

• - Bestimmen eines vordefinierten Abstands zwischen einem ersten Ende und einem zweiten Ende der Schaltpunktverlängerung, wobei die Schaltpunktverlängerung dazu eingerichtet ist, das Messgerät an einem ersten Ende der Schaltpunktverlängerung anzuordnen;
• - Montieren der Schaltpunktverlängerung an einem Messort, wobei die Schaltpunktverlängerung eine Vielzahl von hohlen Rohrelementen aufweist, welche mittels eines Verbindungselements verbunden werden.

Another aspect of the invention relates to a method for producing a switching point extension for a measuring device for level measurement, for level determination and / or for pressure measurement, with the steps:

• Determining a predefined distance between a first end and a second end of the switching point extension, the switching point extension being set up to arrange the measuring device at a first end of the switching point extension;
• - Mounting the switching point extension at a measuring location, the switching point extension having a plurality of hollow tubular elements which are connected by means of a connecting element.

The predefined distance can be determined before and / or during the assembly of the switching point extension at the measuring location.

Another aspect of the invention relates to the use of a switching point extension as described above or below or a method as described above or below for positioning a measuring device for level measurement or for level determination, an impedance limit switch, a vibration limit switch, a measuring device with a high-frequency front, ultrasonic front or laser front-end, and / or a radiometric measuring device.

For further clarification, the invention is described on the basis of embodiments shown in the figures. These embodiments are only to be understood as an example, but not as a limitation.

Figure list

• 1a eine schematische Skizze einer ersten Ausführungsform;
• 1b eine weitere schematische Skizze der ersten Ausführungsform;
• 2a eine schematische Skizze einer zweiten Ausführungsform;
• 2b eine weitere schematische Skizze der zweiten Ausführungsform;
• 3 ein Verfahren gemäß einer Ausführungsform.

It shows:

• 1a a schematic sketch of a first embodiment;
• 1b another schematic sketch of the first embodiment;
• 2a a schematic sketch of a second embodiment;
• 2 B another schematic sketch of the second embodiment;
• 3rd a method according to an embodiment.

Detailed description of embodiments

1a shows a schematic sketch of a first embodiment of a switching point extension 30th . This embodiment is designed to be telescopic. At a first end 31 the switching point extension 30th is a measuring device 10th arranged. At a second end 32 is evaluation electronics 20 arranged. For embodiments where the measuring device 10th The switch point extension can be arranged inside a container 30th at the second end 32 be connected to the container. The switching point extension 30th has a variety of hollow tubular elements 33 on. Two pipe elements each 33 are each by means of a connecting element 34 connected. The fasteners 34 can be of the same or different designs. The connecting element 34 can be designed, for example, as a bayonet lock or as a screw connection. The screw connection can, for example, be an external thread of the smaller tubular element 33 include that in an internal thread of the larger tubular element 33 intervenes. The internal thread can also act as a sealing element 35 be executed. The sealing element 35 can also be in sections outside and in sections outside on the larger tubular element 33 be arranged so that there is, for example, one end of the larger tubular element 33 embraces. The pipe elements 33 can be releasably or non-releasably connected.

1b shows a further schematic sketch of the first embodiment of the switching point extension 30th , where the telescopic pipe elements 33 are pushed into each other. In this form, the switching point can be extended 30th for example, can be transported in a simple manner. For positioning the switching point extension 30th become the telescopic pipe elements 33 by means of the connecting elements 34 connected to a predetermined distance of the first end in this way 31 from the second end 32 to achieve.

2a shows a schematic sketch of a second embodiment of a switching point extension 40 . This embodiment is designed to be segmentable. At a first end 41 the switching point extension 40 is the measuring device 10th arranged. At a second end 42 is the evaluation electronics 20 arranged. The pipe elements 43 have essentially the same outer diameter. The pipe elements 43 are with connecting elements, connecting sleeves or fixing elements 44 connected. The fasteners 44 have a sealing element in this embodiment 45 on. For positioning the switching point extension 40 become the segmentable pipe elements 43 by means of the connecting elements 44 connected to a predetermined distance of the first end in this way 41 from the second end 42 to achieve.

2 B shows a further schematic sketch of the second embodiment of the switching point extension 40 where the pipe elements 43 are omitted to make the electrical connections clear. There is an expandable cable 48 visible, which is designed as a spiral cable and in many embodiments - also in telescopic embodiments - within the tubular elements 43 is led. The stretchable cable 48 has electrical plugs 47 on, which are set up in electrical sockets 46 to be plugged in. In some embodiments, the cable is 48 with the measuring device 10th and / or the evaluation electronics 20 firmly connected so that no connector is used for this connection. Due to the design as a stretchable cable 48 can also make the electrical connection to different lengths of the segmentable switching point extension 40 (or the telescopic switching point extension 30th ) be adjusted.

3rd shows a flow chart 50 a method according to an embodiment. In one step 51 is for a switching point extension 30th , 40 a distance determines between a first end 31 , 41 and a second end 32 , 42 the switching point extension 30th , 40 . Here is the switching point extension 30th , 40 set up the meter 10th at a first end 31 , 41 the switching point extension 30th , 40 to arrange. The distance mentioned can be selected, for example, so that the measuring device 10th is in an optimal location for a certain class of measurements. The class of measurements can be, for example, a level measurement or a level determination of a product in a specific container.

In one step 52 becomes the switching point extension 30th , 40 mounted at a measuring location. It is possible that the distance between the first end during assembly 31 , 41 and the second end 32 , 42 again, if necessary more often. The distance between the first end 31 , 41 and the second end 32 , 42 the switching point extension 30th , 40 using a variety of hollow tubular elements 33 , 43 manufactured. Two each from the large number of hollow tubular elements 33 , 43 by means of one connecting element each 34 , 44 connected.

In one embodiment, the switching point extension is 30th telescopic design.

In one embodiment, the switching point extension is 40 executed segmentable.

In addition, it should be pointed out that “comprehensive” and “having” do not exclude other elements or steps, and the indefinite articles “a” or “an” do not exclude a large number. Furthermore, it should be pointed out that features or steps that have been described with reference to one of the above exemplary embodiments can also be used in combination with other features or steps of other exemplary embodiments described above. Reference signs in the claims are not to be regarded as restrictions.

Reference list

10th

Measuring device

20

Evaluation electronics

30th

Switch point extension

31

first end of the switching point extension

32

second end of the switching point extension

33

Pipe elements

34

Fastener

35

Sealing element

40

Switch point extension

41

first end of the switching point extension

42

second end of the switching point extension

43

segmentable pipe elements

44

Fixing element, connecting element

45

Sealing element

46

electrical sockets

47

electrical plugs

48

stretchable cable

50

flow chart

51, 52

step

Claims (14)

Switching point extension (30, 40) for positioning a measuring device (10) for level measurement, for level determination and / or for pressure measurement, comprising the switching point extension (30, 40): a plurality of hollow tubular elements (33, 43), a connecting element (34, 44) which is set up to connect two tubular elements (33, 43) each, a line arrangement (47, 48) which is set up for connection to a measuring device (10) when the measuring device (10) is attached to a first end (31, 41) of the switching point extension (30, 40), wherein the switching point extension (30, 40) is set up to, when the measuring device (10) is attached to the first end (31, 41) of the switching point extension (30, 40), at a predefined distance from a second end (32, 42) to position the switching point extension (30, 40). Switch point extension (30, 40) after Claim 1 , wherein the connecting element (34, 44) comprises a sealing element (35, 45). Switch point extension (30, 40) after Claim 1 or 2nd The line arrangement (47, 48) comprises: an expandable cable (48) with a plug (47), the expandable cable (48) and the plug (47) being set up to establish an electrical connection between the measuring device (10) and to manufacture evaluation electronics (20) attached to the second end (32, 42). Switch point extension (30, 40) after Claim 3 wherein the stretchable cable (48) is routed inside the plurality of hollow tubular members (33, 43). Switching point extension (30) according to one of the Claims 1 to 4th , wherein the tubular elements (33) are designed such that the inner diameter of a first tubular element (33) is larger than the outer diameter of a second tubular element (33). Switch point extension (30) after Claim 5 , wherein the sealing element (35) has a clamping element. Switching point extension (40) according to one of the Claims 1 to 4th , wherein the tubular elements (43) have a substantially identical outer diameter. Switch point extension (40) after Claim 7 , wherein the connecting element (44) has an internal thread which is set up to engage in an external thread of the tubular elements (43). Switching point extension (30) according to one of the preceding claims, wherein the switching point extension (30) is made telescopic. Switching point extension (40) according to one of the preceding claims, wherein the switching point extension (40) is designed to be segmentable. Level measuring device, point level sensor or pressure sensor, having a switching point extension (30, 40) according to one of the Claims 1 to 10th . Level measuring device, point level sensor or pressure sensor Claim 10 , designed as guided radar, TDR, or as a vibration limit switch or as a pressure measuring device. Method for producing a switching point extension (30, 40) for a measuring device (10) for level measurement, for level determination and / or for pressure measurement, with the steps: - Determining a distance between a first end (31, 41) and a second end (32, 42) of the switching point extension (30, 40), the switching point extension (30, 40) being set up to connect the measuring device (10) to a first Arrange end (31, 41) of the switching point extension (30, 40); - Mounting the switching point extension (30, 40) at a measuring location, the distance between the first end (31, 41) and the second end (32, 42) of the switching point extension (30, 40) using a plurality of hollow tubular elements (33, 43) is produced, and two each of the plurality of hollow tubular elements (33, 43) are connected by means of a connecting element (34, 44). Use of a switching point extension (30, 40) according to one of the Claims 1 to 10th or a procedure Claim 13 for positioning a measuring device (10) for level measurement, for level determination and / or for pressure measurement.

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