CROSS REFERENCE TO RELATED APPLICATIONS

This application claims foreign priority under 35 U.S.C. § 119(a)-(d) to Application No. DE 102019119414.8 filed on Jul. 17, 2019, the entire contents of which are hereby incorporated by reference.

TECHNICAL FIELD

Disclosed is a tampering detection system for a dispensing nozzle of a dispensing system, wherein the dispensing nozzle is inserted into a connecting piece of the dispensing system. A method for detecting tampering with a dispensing nozzle of a dispensing system is also disclosed.

BACKGROUND

Dispensing systems by which, for example, pourable food can be filled into packagings or other containers, comprise at least one dispensing nozzle that is inserted into a connecting piece that is provided on the system side. During the dispensing process, the food flows out of the dispensing nozzle into the packagings or the other containers. In this context, it is important from the perspective of food safety for the dispensing nozzle to be positioned correctly inside the connecting piece and, in particular, not to have been subsequently tampered with.

SUMMARY

An object is to provide a tampering detection system for a dispensing nozzle of a dispensing system as well as a method for detecting a tampering with a dispensing nozzle of a dispensing system such that any tampering with the dispensing nozzle can be reliably detected by the tampering detection system in an easy and cost effective way.

An inventive tampering detection system for a dispensing nozzle of a dispensing system, wherein the dispensing nozzle is inserted into a connecting piece of the dispensing system, comprises a flat, tactile sensor that has a number n≥2 of pressure sensitive and individually evaluable sensor segments and that extends along an inner circumference of the connecting piece in a connecting region for the dispensing nozzle and that is arranged between the connecting piece and the dispensing nozzle, as well as an evaluation unit, which is connected to the sensor segments and is designed to detect for each of the sensor segments a pressure acting on the respective sensor segment. The disclosed tampering detection system can be used to detect any subsequent tampering with the dispensing nozzle, in particular, the attempt to loosen the dispensing nozzle from the connecting piece of the dispensing system in a very simple way, in particular, also in an automated manner. The tactile sensor can have preferably four sensor segments that can be made, in particular, the same size, so that in the case of a dispensing nozzle with a circular cross section each of the four sensor segments covers an angular range of 90°. The tactile sensor can be attached to the inner face of the connecting piece in a number of different ways. For example, it is possible for the tactile sensor to be glued to the inner face of the connecting piece in the connecting region for the dispensing nozzle. As an alternative, it is also possible to provide, for example, a clamping ring that is inserted into the connecting piece during assembly and is designed to fix the tactile sensor in its desired mounting position in a clamping manner on the inner face of the connecting piece before the dispensing nozzle is mounted at a later time.

In principle, a combination of an adhesive connection with a clamping connection, which can be implemented, in particular, by the clamping ring, is also possible. The dispensing nozzle is inserted into the receiving opening of the connecting piece and, when correctly mounted, exerts a relatively uniform pressure on all of the sensor segments of the tactile sensor, especially if the connecting piece and the dispensing nozzle have a circular cross section. If then the evaluation unit detects in essence the same level of pressure for each of the sensor segments, then the dispensing nozzle is correctly mounted and is in its desired mounting position. In this case, the tightness of the arrangement is ensured by the dispensing nozzle itself that is mounted so as to fit precisely inside the connecting piece. If the dispensing nozzle were to be subsequently tampered with and were no longer in its desired mounting position, then at least one of the sensor segments will detect a pressure that has changed significantly with respect to the correctly mounted state of the dispensing nozzle. The pressure change is evaluated by the evaluation unit and converted by the evaluation unit preferably into a corresponding response measure. Possible response measures to this event may be, for example, the automated shutting down of the dispensing system and/or the output of a warning message or, more specifically, a warning signal.

The tactile sensor in one advantageous embodiment comprises a first layer and a second layer, with the two layers being provided with electrically conductive electrodes that are spaced apart from one another by a compressible, pressure sensitive intermediate layer, so that the compression of the intermediate layer causes a change in the electrical property between the electrodes that is detectable by the evaluation unit. The intermediate layer is designed such that it is compressed by the action of a compressive force that is generated by the dispensing nozzle inserted into the connecting piece. This compression causes a change in the electrical property between the electrodes that is detectable by the evaluation unit; and the changed property is a measure for the amount of pressure that is exerted on the individual sensor segments. The intermediate layer may include, for example, compressible elements, so that when subjected to a level of pressure that exceeds a defined limit value that is specified by the elasticity properties of the intermediate layer, the electrodes of the two layers are pressed against each other; and, as a result, this may lead to a direct contact between the electrodes. When the dispensing nozzle is correctly mounted, the electrodes are pressed against each other preferably in all of the sensor segments, so that the electrodes are in contact with each other in all of the sensor segments. If the pressure, acting on at least one of the sensor segments, is reduced by at least partially loosening the dispensing nozzle from the connecting piece such that the limit value, required for the electrodes of the sensor segment concerned to be pressed against each other, is undershot, then the electrodes are no longer in contact with each other in the sensor segment concerned. This state can be detected accordingly by the evaluation unit.

In an alternative embodiment, the intermediate layer can also be made from a material that changes its electrical resistance when subjected to compressive loading. Such an intermediate layer can be formed, for example, over the entire surface. Consequently even if the electrodes of the two layers do not make direct contact with each other, this change in resistance can be detected by the evaluation unit that is designed accordingly. By suitably calibrating and assigning the measured electrical resistance values to the pressure values, the pressure in each of the sensor segments can be determined in a relatively accurate way in this embodiment.

The layers that are provided with the electrodes may be designed preferably as a two-dimensional structure, in particular, as a two-dimensional textile structure with electrodes that are made of electrically conductive yarns and are sewn or woven into the two-dimensional textile structure. Such two-dimensional structures, in particular, two-dimensional textile structures, are characterized by a high flexibility, so that the tactile sensor, which is formed by the two layers and the intermediate layer that is disposed between the two layers, can be adapted very easily to the shape of the connecting piece or, more specifically, the dispensing nozzle and, in addition, can also be easily mounted.

In a preferred embodiment, it is proposed that the first layer of the tactile sensor is provided with at least one electrically conductive electrode that extends through all of the sensor segments. Thus, all of the sensor segments in the first layer comprise at least one common electrode, optionally also a plurality of common electrodes.

In a particularly preferred embodiment, there is the option that the second layer of the tactile sensor has a number of electrodes that corresponds to the number of sensor segments or to a multiple of the number of sensor segments. The electrodes of the second layer of the tactile sensor extend preferably orthogonal to the at least one electrode of the first layer, where the at least one electrode is common to all of the sensor segments, so that a matrix-like structure of the sensor segments of the tactile sensor can be obtained; and the matrix-like structure can be evaluated in a relatively easy way by the evaluation unit. In this context, it has been found to be useful in practice for the number of electrodes in the second layer to be identical in each of the sensor segments.

In one advantageous embodiment it can be provided that a pressure reference value, which represents the pressure that is exerted on the respective sensor segments when the dispensing nozzle has been correctly mounted in the connecting piece, is defined for each of the sensor segments in the evaluation unit. This has the background that in the case of certain types and geometric designs of the dispensing nozzle and the connecting piece, such as, for example, in the case of cross-sectional shapes that are longitudinally elliptical and deviate from a circular shape, the pressure values, measured by the sensor segments, may differ from the start. In other words, the pressure values, which are measured in the individual sensor segments, may differ from each other, even though the dispensing nozzle has been correctly mounted inside the connecting piece. However, the pressure reference values may also be identical or rather more or less identical for each of the sensor segments.

In a particularly advantageous embodiment, it may be provided that a tolerance range is defined for each of the pressure reference values of the sensor segments in the evaluation unit. This tolerance range indicates the pressure, up to which the dispensing nozzle may still be considered to be correctly mounted.

An inventive method for detecting a tampering with a dispensing nozzle of a dispensing system, wherein the dispensing nozzle is inserted into a connecting piece of the dispensing system, comprises the steps of:providing a flat, tactile sensor with a number n≥2 of pressure sensitive and individually evaluable sensor segments, where the sensor is positioned in a connecting region for the dispensing nozzle between the connecting piece and the dispensing nozzle such that the sensor extends along an inner circumference of the connecting piece and is subjected to a pressure by the dispensing nozzle that is inserted into the connecting piece,detecting the pressure, exerted on each of the sensor segments, by an evaluation unit that is connected to the tactile sensor, andchecking whether the measured pressure values indicate a tampering with the dispensing nozzle.

The disclosed method makes it possible to check in an easy way whether the dispensing nozzle, which has been inserted into the connecting piece of the dispensing system, may have been perhaps tampered with later on. If the dispensing nozzle has been subsequently tampered with and at least partially loosened, for example, with the use of a screwdriver, then at least one of the sensor segments will detect a pressure, which has changed significantly with respect to the correctly mounted state of the dispensing nozzle; and this pressure change is evaluated by the evaluation unit and is converted into a corresponding response measure. Possible response measures to this event may be, for example, the shutting down of the dispensing system and/or the output of a warning message or, more specifically, a warning signal.

In a preferred embodiment, it is proposed that a pressure reference value, which represents the pressure that is exerted on the respective sensor segments when the dispensing nozzle has been correctly mounted in the connecting piece, is defined for each of the sensor segments in the evaluation unit.

In a particularly preferred embodiment, it can be provided that a tolerance range is defined for each of the pressure reference values of the sensor segments in the evaluation unit. This tolerance range indicates such pressure values, at which the dispensing nozzle may still be considered to be correctly mounted. If the measured pressure of at least one of the sensor segments is outside the tolerance range defined for the sensor segment concerned, then this indicates, in particular, a subsequent tampering with the dispensing nozzle, so that the evaluation unit can initiate the corresponding response measures.

