Dosing device of a process plant

Abstract

Dosing device (1) of a process plant comprising a valve (2) and an evaluation unit (12), wherein the valve (2) in the open state has an annular gap (14) for the passage of a metering medium, wherein the valve (2) has a sensor arrangement, wherein the sensor arrangement comprises at least a light source (9) and a light sensor (10) for detecting a light signal emitted by the light source (9), wherein the sensor arrangement is arranged such that a light signal emitted by the light source (9) is emitted into the annular gap (14) when the valve (2) is open, and wherein the dosing device (1) has an evaluation unit (12) which is configured to monitor the closing state of the valve (2) using the sensor arrangement, characterized by that the closure part (8) has the light source (9) of the sensor assembly.

Description

[0001] The invention relates to a dosing device of a process plant according to the preamble of claim 1. A generic dosing device is disclosed in DE 197 42 062 A1 or DE 201 16 202 U1.

[0002] DE 39 39 502 A1 discloses a filter device comprising a valve. The valve has a light barrier arrangement. The light barrier arrangement serves to detect the number of particles in a liquid as it passes through the valve area and to estimate the quality of the previous filtration.

[0003] Dosing devices in process plants typically use seals in the valves. These seals can be subject to wear due to mechanical abrasion and contamination. This can cause the valve to leak, making it impossible to accurately determine the dosing quantity during dosing processes and leading to a loss of dosing medium.

[0004] Based on the previous prior art, it is now the object of the present invention to provide a dosing device in a process plant in which such leaks can be detected.

[0005] The present invention solves this problem by a dosing device of a process plant having the features of claim 1.

[0006] A dosing device according to the invention for a process plant can, in a preferred embodiment, be designed as a filling system. It comprises a valve and an evaluation unit. The valve can have a closed state and an open state. The open state can mean a complete or partial opening of the valve. In the open state, the valve has an annular gap. A filling medium can be passed through this annular gap through the valve. The valve has a sensor arrangement. This sensor arrangement comprises at least one illuminant and a light sensor for detecting a light signal emitted by the illuminant. The sensor arrangement is arranged such that the light signal emitted by the illuminant is emitted into the annular gap when the valve is open.The dosing device also has an evaluation unit configured to monitor the valve's closed state using the sensor array. The light sensor detects the emitted light signal and transmits a measurement signal to the evaluation unit. The evaluation unit uses the measurement signal to determine whether the valve is sealed and closed or whether it is leaking. According to the invention, the closure part includes the illuminant of the sensor array.

[0007] Unlike the prior art, there is no measurement of particle concentration but rather a monitoring of the closing state, in particular the tightness of the closing state.

[0008] Advantageous embodiments of the invention are the subject of the subclaims.

[0009] It is advantageous if the evaluation unit adjusts the valve for filling a container with a metered medium, particularly a medium to be filled, according to a predefined dosing curve, particularly a predefined filling curve. This dosing curve can be stored, for example, in a data storage device in the evaluation unit. A flow meter can determine the flow rate during dosing, particularly during filling, compare it with the theoretical value on the dosing curve, and adjust the valve accordingly.

[0010] The dosing device in a process plant can have a flow meter for determining one or more flow measurement signals. The valve can also be designed to be controllable by the evaluation unit based on the determined flow measurement signals.

[0011] The valve can preferably have a closure part, in particular a linearly movable closure part, and a valve wall, in particular a valve wall in contact with the medium. "Contact with the medium" refers to the metering medium during normal operation of the metering device in a process plant. The closure part and the valve wall advantageously limit the annular gap when the valve is open.

[0012] The valve wall may contain the light sensor.

[0013] The lamp can have one or more light sources and a ring-shaped light guide. The light guide is the section of the lamp that comes into contact with the medium.

[0014] Alternatively, the illuminant may also comprise a plurality of light sources which are arranged circumferentially, preferably uniformly, around the closure part.

[0015] In a preferred and advantageously energy-saving variant of the invention, the illuminant can have at least one light source which is designed as an LED light source.

[0016] Alternatively or additionally, the light source can be designed to emit UV light. This allows disinfection of at least a portion of the valve through the emitted UV light. Alternatively or additionally, the light source can also be designed to emit light in the visible spectrum, so-called Visible light or visual light.

[0017] The evaluation unit can advantageously be configured to emit an alarm signal upon detection of an insufficient closing state of the valve.

[0018] It is also advantageous if the valve is designed as a double seat valve.

[0019] Alternatively, or preferably additionally, the sensor arrangement can also be configured for reflection measurement. In this case, the light source and the light sensor can be arranged on the same side of the annular gap. While a transmitted light measurement is performed in the aforementioned variant, it may be advantageous to perform a reflection measurement in some applications.

[0020] Different media may require different sensor arrangements. Typical examples of media diversity include milk, beer, cherry juice, water, and / or a drained line containing air or steam. For media with intense intrinsic color, measuring reflected light can prove significantly more reliable than measuring transmitted light. Especially during filling, checking valve tightness using reflected light is recommended. However, for other applications in a process plant, valve tightness can also be determined using transmitted light at the valve seat.

[0021] The invention is explained in more detail below using an exemplary embodiment with the aid of the attached figures. They show: Fig. 1 a dosing device according to the invention comprising a valve; and Fig. 2 Detailed view of the valve of the Fig. 1.

[0022] Within the scope of the present invention, the term "dosing device" also includes filling systems. When dosing with the dosing device according to the invention, a second valve, a container, and / or a pump can sometimes be installed after the first valve 2 described below. In a filling system, the valve 2 shown typically often forms the barrier to ambient light. Both variants are encompassed by the term "dosing device" within the scope of the present invention.

[0023] Fig. Figure 1 shows a first embodiment of a dosing device 1 according to the invention in a process plant. The dosing device 1 in a process plant has a tank 3 containing the dosing medium to be filled. This can, for example, involve filling a beverage. However, other flowable media can also be filled. The dosing medium is directed into a container 5 to be filled, e.g., a bottle.

[0024] The dosing device 1 in a process plant has an outlet opening 11. An evaluation unit 12 monitors the filling and controls the dosing process.

[0025] To regulate the dosing quantity and the dosing speed, the dosing device 1 in a process plant has a valve 2. This valve can be designed as a single-seat valve or, particularly preferably, as a double-seat valve.

[0026] The valve 2 has a valve wall 13 and a closure part 8. The valve wall 13 and the closure part 8 define an annular gap 14 through which the dosing medium is passed when the valve 2 is open.

[0027] This closure part 8 is arranged to be movable, preferably linearly movable in or against a direction S, in the valve, in particular a cylindrical valve wall 13. A drive (not shown in detail), e.g., an air-spring drive, can be used to move the closure part 8. A piston rod can also be provided, which connects the drive to the closure part 8. For reasons of clarity, the drive and the piston rod are shown in Fig. 1 and Fig. 2 is not presented or discussed in detail.

[0028] In Fig. 1 and Fig. In Figure 2, the closure part 8 is depicted as piston- or plug-shaped, particularly truncated cone-shaped. However, the closure part 8 may also have a different shape.

[0029] According to the invention, the closure part 8 has a light source 9 that emits light into the annular gap 14. The light source 9 emits a light signal to one or more light sensors 10. The light sensor 10 emits a measurement signal to the evaluation unit 12.

[0030] The illuminant 9 preferably comprises one or more light sources and an annular light guide. Alternatively or additionally, the illuminant 9 comprises several light sources, which are arranged circumferentially, preferably uniformly, around the closure part 8.

[0031] Reflection measurement is also conceivable within the scope of the present invention. The light signal from the illuminant is reflected back to the light sensor. In this variant, the light sensor is arranged on the same side of the annular gap as the illuminant. The light sensor can even form a structural unit with the illuminant.

[0032] In a particularly preferred embodiment, the light source can be an LED lamp. Alternatively or additionally, the light source or another light source can be designed as a UV lamp. The UV radiation also provides a disinfecting effect.

[0033] Furthermore, in a preferred embodiment, the dosing device 1 in a process plant comprises a flow meter 4. The flow meter 4 can be designed, for example, as a magnetic-inductive flow meter. Therefore, the Fig.The flow meter 4 shown in Figure 1 comprises a pair of electrodes 6 and a magnet system 7.

[0034] The evaluation unit 12 controls the dosing process of the dosing medium into the container 5 to be filled based on the measured values ​​determined by the flow meter 4 and adjusts the flow during filling by actuating the valve 2.

[0035] The evaluation unit 12 also determines the tightness of the valve 2 in the closed state based on the light sensor 10 and the light source 9. The intensity of the received light signal changes depending on the medium located between them. If a dosing medium is located between the light source 9 and the light sensor 10, this is determined by the evaluation unit 12 based on the measured values ​​transmitted by the light sensor 10.

[0036] The evaluation unit 12 can then output an alarm signal, e.g., in the form of a visual or acoustic signal. Thus, the light sensor 10 serves to monitor the closed state of a valve. The light sensor 10 monitors the seal of the valve 2. Reference symbol 1 Dosing device in a process plant 2 valve 3 tanks 4 flow meter 5 Container to be filled 6 pairs of electrodes 7 Magnet system 8 locking part 9 bulbs 10 Light sensor 11 Outlet opening 12 Evaluation unit 13 Valve wall 14 Annular gap

Claims

[1] Dosing device (1) of a process plant comprising a valve (2) and an evaluation unit (12), wherein the valve (2) in the open state has an annular gap (14) for the passage of a dosing medium, wherein the valve (2) has a sensor arrangement, wherein the sensor arrangement comprises at least one illuminating means (9) and a light sensor (10) for detecting a light signal emitted by the illuminating means (9), wherein the sensor arrangement is arranged such that a light signal emitted by the illuminant (9) is emitted into the annular gap (14) when the valve (2) is in the open state, and wherein the dosing device (1) has an evaluation unit (12) which is designed to monitor the closing state of the valve (2) using the sensor arrangement, characterized by , that the closure part (8) has the illuminant (9) of the sensor arrangement. [2] Dosing device according to claim 1, wherein the valve (2) has a closure part (8) and a valve wall (13), and wherein the closure part (8) and the valve wall (13) delimit the annular gap (14) in the open state of the valve (2). [3] Dosing device according to claim 1 or 2, wherein the valve wall (13) has the light sensor (10). [4] Dosing device according to one of claims 1 to 3, wherein the illuminating means (9) comprises one or more light sources and an annular light guide. [5] Dosing device according to one of claims 1 to 3, wherein the illuminating means (9) has a plurality of light sources which are arranged circumferentially distributed around the closure part (8). [6] Dosing device according to one of claims 1 to 5, wherein the evaluation unit (12) is arranged to emit an alarm signal upon detection of an insufficient closing state of the valve (2). [7] Dosing device according to one of claims 1 to 6, wherein the sensor arrangement is designed to monitor the closed state on the basis of the light signal emitted and reflected in the annular gap (14).

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