DE102019205393A1 - Sensor for level or limit level measurement - Google Patents

Abstract

A sensor (100) is proposed for determining a fill level and / or limit level of a medium (206) in a container (202). The sensor (100) has a sensor unit (102) for emitting and / or receiving a measurement signal, an evaluation unit (106) for determining the fill level and / or the limit level, and a housing (112) with at least one housing area (114), which is designed in such a way that the measurement signal can be transmitted through the housing area (114). The housing also has an attachment area (116) for attaching the sensor (100) to the container (202), the attachment area (116) having a plastic web (120) surrounding at least part of the housing area (114) so that the The sensor (100) can be attached and / or fastened to the container (202) by melting at least part of the plastic web (120) by means of plastic welding.

Description

Field of invention

The invention relates generally to the field of level measurement and / or limit level measurement. In particular, the invention relates to a sensor for determining a fill level and / or a limit level of a medium in a container.

Background of the invention

Sensors for determining the level and / or limit level of a medium in a container are often based on a transit time method. Such transit time-based sensors send a measurement signal, for example a radar signal or an ultrasonic signal, in the direction of the surface of the medium, with part of the measurement signal being reflected on the surface and being able to be received by the sensor. The transit time of the measurement signal from the sensor to the surface of the medium and back is proportional to the length of the path covered, so that the filling level and / or the reaching of a limit level of the medium can be determined based on the transit time of the measurement signal.

Radar-based sensors in particular generally have an antenna for emitting and / or receiving the measurement signal. Radar sensors are therefore often attached to the containers in such a way that the antenna protrudes into the interior of the container. This regularly requires complex fastening of the sensor to the container and suitable sealing of the fastening point. Radar sensors, in particular the associated antennas, can also be installed at a certain distance from the container. However, environmental influences, such as moisture on the container, can lead to disruptive influences or a disruption of the measurement. A lot of installation space can also be required here, for example by attaching a sensor.

Summary of the invention

With embodiments of the invention, an improved sensor for level and / or limit level measurement can advantageously be provided. The sensor according to the invention can be characterized in particular by a compact design, robustness, longevity and increased measurement accuracy.

This is made possible in particular by the subject matter of the independent patent claim. Further developments of the invention result from the dependent claims and the following description.

One aspect of the present disclosure relates to a sensor for determining, ascertaining and / or measuring a fill level and / or limit level of a medium in a container. The container can be made at least partially, in particular completely, from plastic. The medium can be a liquid, a filling material and / or a bulk material. The sensor has a sensor unit, also called sensor circuit and / or sensor electronics below, for emitting and / or receiving a measurement signal. Furthermore, the sensor has an evaluation unit for determining the fill level and / or the limit level based on a transit time determination of the measurement signal. The evaluation unit can be set up, for example, to determine a transit time between sending the measurement signal and receiving a portion of the measurement signal reflected on the medium. Based on the determined transit time, the evaluation unit can determine a signal and / or a measured value that correlates with the fill level and / or the limit level. Furthermore, the sensor has a housing with at least one housing area which is designed to be arranged opposite a container wall of the container in order to measure the fill level and / or the limit level. In other words, the sensor can be designed such that it can be attached to the outside of the container wall of the container, so that the housing area is opposite the container wall. The housing area and / or the housing is designed such that the measurement signal can be transmitted through the housing area and / or through the housing. The housing also has a fastening area, at least partially made of plastic, for fastening and / or mounting the sensor to the container, the fastening area having a plastic web encircling at least part of the housing region, so that the sensor can be melted by at least part of the plastic web Plastic welding can be attached and / or fastened to the container, in particular permanently and / or permanently fastened.

The plastic web can for example denote a material web made of plastic and / or a plastic area of the housing and / or the fastening area, which is arranged on the outside of the housing. The plastic web can protrude at least partially from the housing or end flush with the housing area. The plastic web can encircle the housing area through which the measurement signal can be transmitted, for example along an outer circumference of the housing and / or the housing area. The fastening area and / or the plastic web of the fastening area can adjoin the housing area or be at least partially spaced from the housing area. The fastening area and / or the plastic web can form a weld-preparing structure, a weld-seam-preparing structure and / or a weld seam preparation of the housing and / or the sensor, which enables the sensor to be attached to the container and / or the container wall of the container by means of a plastic welding process with the formation of a Allows welded connection and / or a weld seam between the housing and the container. Any plastic welding process can be used for this. For example, the sensor can be attached to the container by ultrasonic welding by applying a sonotrode. The sensor can also be attached by means of laser transmission welding, in particular if one of the two welding partners is transparent in terms of its wavelength for the laser used. The other welding partner should not be transparent for this wavelength, but should be able to absorb the energy of the laser. Hot gas welding by melting a welding filler material or a welding nose, for example by means of a torch, heating element welding and / or rotational friction welding, can also be used, the latter especially if the sensor is attached to the container with a round and / or circular weld seam.

For example, here and in the following, the plastic web can denote an energy director, a weld seam preparation and / or a weld metal, for example if the plastic web is at least partially melted.

By attaching the sensor to the container by means of plastic welding, an integral, robust, resistant and / or solid physical connection between the housing of the sensor and the container can advantageously be established. In particular, if the container wall and the fastening area of the housing are made of the same type of plastic, for example similar thermoplastics, a high strength of the joint or welded connection can be ensured. The weld seam can also be used to reliably seal an intermediate space between the housing area of the sensor and the container wall, so that in particular no dust, moisture and / or other media can penetrate into this intermediate space. Interferences which could negatively influence the measurement and / or a quality of the measurement can thus be kept low or completely avoided. In addition, the weld seam formed between the housing of the sensor and the container can have the same properties in terms of resistance to environmental influences as the housing itself, so that the sensor can remain on the container permanently, for example over the entire service life of the sensor. By welding the sensor to the container, further components for fastening the sensor, such as adhesive, can also be dispensed with. The use of different materials for fastening the sensor can thus be avoided, which can be advantageous in particular when the sensor is used in chemical-loaded environments, for example because different materials can react differently to chemicals. The omission of further components for fastening the sensor, such as, for example, adhesive, can also result in cost savings, in particular in the case of large quantities. A joining process or fastening process for fastening the sensor to a container can also be automated and can also be characterized by a short duration of the welding process, so that the installation time and / or the installation effort for assembling the sensor can be reduced. Furthermore, the sensor can only be separated from the container by destroying at least part of the housing. The sensor can sometimes become unusable as a result and / or optically recognizable abnormalities can occur on the sensor housing, so that a manipulation of the connection between the sensor and the container can be recognized. The welded connection between the sensor and the container can thus also offer protection against theft and / or vandalism. Also, because the sensor is welded on, approval of the sensor by state authorities can be simplified and / or accelerated, for example because no third component, such as adhesive, has to be tested and / or approved as part of approval. Furthermore, new applications can be opened up, since the sensor of this invention can be installed inexpensively, for example since no additional fastening material is necessary. The sensor according to the invention can thus be of interest for applications in which conventional, automatic level measurements are too expensive.

The housing area can generally denote part of the housing, for example part of a housing surface, a housing surface, a housing side, part of a housing side, part of a housing wall and / or a housing wall. The measurement signal can be emitted and / or received through the housing area. At the same time, the housing area can designate an emission area and / or reception area of the housing of the sensor. The housing area and / or a housing wall in the housing area can, for example, have a wall thickness and / or thickness of around 1 mm to 5 mm, with fundamentally any dimensions being possible. A wall thickness of the housing area can be less than a wall thickness of another sub-area of the housing.

The evaluation unit can generally denote evaluation electronics, an electronic evaluation unit and / or an evaluation circuit. The evaluation unit is set up to determine and / or determine a signal that correlates with the level and / or the limit level based on the transit time and / or based on a transit time measurement between the emission and reception of the measurement signal. This signal can designate at least one parameter that correlates with the limit level and / or the fill level. The signal correlating with the level and / or the limit level and / or the at least one parameter can in particular be representative and / or indicative of the transit time between the emission of the measurement signal and the reception of the measurement signal reflected from the product surface (or the surface of the medium) , for the level of the product in the container, for the limit level of the product, for reaching the limit level and / or for exceeding a fill level or limit level.

To determine the signal correlating with the level and / or the limit level, the evaluation unit can use both analog and digital signal processing methods. Accordingly, the evaluation unit can have, for example, an amplifier, low-pass filter, frequency mixer and / or band-pass filter for analog signal processing. Furthermore, the evaluation unit can have one or more analog-digital converters that can sample and quantize analog signals. In addition, the evaluation unit can have at least one processor for digital signal processing, for example a microprocessor, a digital signal processor or a processor with application-specific instruction sets (application specific instruction set processors - ASIPs). In addition, the evaluation unit can have at least one dedicated memory module for data and / or program code, in particular volatile or non-volatile memories. Furthermore, the evaluation unit can have an application-specific integrated circuit (ASIC).

According to one embodiment, the sensor is designed as a radar sensor. The measurement signal can thus designate a radar signal which can be emitted by the sensor unit through the housing area of the housing in the direction of the medium. The measurement signal can also be transmitted through the container wall. A part of the measurement signal can be reflected on a surface of the medium and at least partially pass through the container wall and through the housing area and thus be received by the sensor unit. The radar signal can generally designate a transmission signal which can be emitted by the radar sensor and / or the sensor unit in the direction of the filling material and a reception signal which can be reflected on the medium and received by the sensor unit. The received signal can designate the part of the transmitted signal reflected by the filling material. At the same time, the sensor unit can be set up to emit the transmission signal in the direction of the filling substance and / or to receive the received signal reflected on the filling substance. For this purpose, the sensor unit can have an antenna. For example, a parabolic antenna, a horn antenna, a Cassegrain antenna or a patch antenna can be used. The sensor unit can also have an antenna group, wherein a directional characteristic of the antenna group can optionally be adaptively adaptable in order to achieve beam focusing, for example.

The antenna of the sensor unit can be designed both to emit the measurement signal, the radar signal and / or the transmission signal and to receive the measurement signal, radar signal and / or the received signal reflected from the product surface (or the surface of the medium). For this purpose, the sensor unit can, for example, have a transmit / receive switch (duplexer), which can be designed and / or set up to time-discriminate the transmit signal and the receive signal. However, it is also possible for the sensor unit to have different antennas for transmitting and receiving the radar signal, which antennas can optionally be spatially separated from one another.

The invention can in particular be viewed as being based on the knowledge described below. If an electronic sensor, for example a sensor that works with the physical measuring principle of radar measurement, is implemented in a housing that is at least partially made of plastic, there are several options for mounting such a sensor, in particular when mounting the sensor on a container, which also consists at least partially of plastic and / or has a container wall consisting of a polymeric, thermoplastic material. One possibility of mounting is to attach the sensor to the container with a third component of some kind. For example, an adhesive or mechanical fastening elements such as screws can be used. Such third components should, however, meet the same requirements with regard to environmental influences as a housing material and / or a material of the housing of the sensor. In particular, possible temperature fluctuations and / or solar radiation can impair the fastening of the sensor. In the case of adhesive bonding, it may also be necessary, for example, a large-area contact between the sensor and the container produce so that the adhesive can build up a sufficient adhesive bond and a corresponding bond strength. For this purpose, correspondingly large, plane-parallel surfaces of the sensor and the container wall may be required. In contrast, when the sensor is welded to a container, a reliable, robust and permanent attachment of the sensor to the container can be made possible.

According to one embodiment, the sensor is designed as an ultrasonic sensor. In this embodiment, the measurement signal can therefore denote an ultrasonic signal which, analogous to the explanations given above on the radar signal, can be irradiated through the housing, the housing area and / or the container wall in the direction of the medium, a portion of the ultrasonic signal reflected on the medium in turn from the sensor unit can be received.

According to one embodiment, the fastening area and / or the plastic web completely surrounds the housing area. For example, the fastening area and / or the plastic web can encircle the housing area and / or follow any other geometry. By welding the sensor to the container, a weld seam can therefore be formed that runs completely around the housing area. Thus, the housing area and / or an intermediate space between the housing of the sensor and the container can be reliably and permanently sealed and / or protected from environmental influences after the sensor has been welded to the container. This in turn can increase the service life of the sensor at a measuring point and / or the quality of the measurement, for example because interference, such as the penetration of moisture and / or dust into the space between the sensor and the container, can be avoided.

According to one embodiment, the fastening area and / or the plastic web has at least one bevel and / or at least one beveled surface. By forming a bevel and / or a beveled surface, a welding process for attaching the sensor to the container can advantageously be simplified, improved and / or accelerated. The chamfer and / or the beveled surface can also ensure reliable formation of a closed weld seam and / or weld connection. This in turn can have an advantageous effect on the mechanical strength of the welded connection.

According to one embodiment, the fastening area and / or plastic web is designed as an energy direction transmitter for producing, by means of plastic welding, an integral welded connection between the sensor and the container wall. By designing the plastic web as an energy director, among other things, a welding direction for welding the sensor to the container can be specified and / or predetermined. This in turn can enable a closed welded connection to be formed in a defined manner, in particular since a fusing area at which the plastic web begins to melt during the welding process can be predetermined by the energy director and / or its geometry.

According to one embodiment, the fastening area and / or the plastic web has a triangular cross-section and / or a triangular cross-sectional geometry. An edge of the plastic web can protrude from the housing and / or the fastening area. The edge of the plastic web can form a melting area at which the plastic web begins to melt during the welding process. This allows the sensor to be precisely placed and attached to a container. As an alternative or in addition, the fastening area and / or the plastic web can have, for example, a serrated geometry. Overall, the fastening area and / or the plastic web can preferably be designed in such a way that contact with the container wall is limited to the smallest possible area so that a lot of energy can be bundled there during the welding process and the plastic can be melted in a targeted manner.

According to one embodiment, the cross section of the fastening area and / or the plastic web is symmetrical. The plastic web can therefore have a symmetrical, triangular cross-section.

According to one embodiment, the cross section of the fastening area and / or of the plastic web is asymmetrical on one side. The plastic web can therefore have a triangular cross-section which is asymmetrical on one side.

• - ein erstes Gehäuseteil, welches den Gehäusebereich aufweist und/oder ausbildet, und
• - ein zweites Gehäuseteil, welches den Befestigungsbereich aufweist und/oder ausbildet.

According to one embodiment, the housing is designed in at least two parts, the housing having:

• - A first housing part, which has and / or forms the housing area, and
• - A second housing part which has and / or forms the fastening area.

The first housing part is detachably connected and / or connectable to the second housing part. For example, the first housing part can be connected to the second housing part by means of a snap connection, a clamping connection, a screw connection, an adhesive connection or a any other connection. A connection point between the first housing part and the second housing part can also be sealed with one or more seals. The second housing part can form an adapter which can be attached to a container by means of plastic welding. After the second housing part has been fastened to the container, the first housing part can then be connected to the second housing part. The first housing part can in particular enclose the sensor unit and the evaluation unit, for example completely enclose them, so that the sensor unit and the evaluation unit can be reliably protected against environmental influences.

In general, the housing can be made at least partially from plastic. However, it is also conceivable that at least part of the housing is made of metal or some other material.

According to one embodiment, the housing is made in one piece from plastic. This can enable inexpensive manufacture in a compact and robust design. For example, the housing of the sensor can be injection-molded in one piece from plastic. A housing injection-molded in one piece from plastic can be particularly advantageous since it has no connection points at which different housing components are connected to one another and at which leaks could occur. Overmoulding the sensor unit, the evaluation unit and / or further components of the sensor to form a one-piece housing can enable a compact and robust design of the sensor.

According to a further embodiment, the housing of the sensor is made entirely from a thermoplastic material. This enables inexpensive production by means of injection molding. In particular, it can be advantageous to manufacture the housing from a plastic with a low relative permittivity (for example 1.5-3) such as polyethylene or polypropylene. This can be advantageous when the sensor is designed as a radar sensor, since it reduces the ringing of the antenna, improves the received signal quality in the close range and thus reduces a blocking distance of the sensor. The blocking distance is the distance within which no or no reliable measurement / evaluation of the measurement signals received is possible.

According to one embodiment, the housing is completely closed. For example, the housing encloses and / or envelops the sensor unit and the evaluation unit completely and / or permanently. In particular, the housing can also enclose an antenna of the sensor unit. The sensor can also have further components, such as a communication unit and / or a power supply unit, which can also be completely enclosed by the housing. The housing of the sensor can in particular be designed in such a way that it cannot be opened. This prevents, for example, aggressive gases or liquids from coming into contact with the sensor unit, the evaluation unit and / or other components through unintentional opening of the housing. The housing that permanently encloses the sensor unit and evaluation unit can thus increase the safety and robustness of the sensor. In addition, the inside of the sensor can be protected from being influenced by third parties, since opening the housing can destroy it.

According to one embodiment, the housing is completely closed. Alternatively or additionally, the housing encloses and / or envelops the sensor unit and the evaluation unit hermetically, in particular dust-tight, water-tight and / or airtight. For example, the housing of the sensor can be designed to achieve protection class IP68, i.e. the housing of the sensor can be dust-tight and offer protection against the ingress of water even if it is continuously submerged. In addition, the housing can be designed and / or designed to prevent gases from penetrating into the interior of the housing. This can be relevant, for example, in plants in the chemical industry in which explosive or corrosive gases can occur.

According to one embodiment, the sensor is designed to be completely wireless to the outside. As an alternative or in addition, the housing does not have a cable bushing. This means that the sensor can, at least temporarily, be operated completely independently and not connected to a cable. This also enables efficient and flexible attachment of the sensor to any container, sometimes also transportable. The installation effort for installing the sensor can also be considerably reduced as a result.

According to one embodiment, the sensor also has a communication unit which is arranged in the housing and which is set up to transmit the measurement signal, a signal correlating with the level and / or limit level and / or a measured value correlating with the level and / or the limit level to transmit through the housing to a recipient. The communication unit of the sensor can be set up to wirelessly transmit the signal, at least one parameter correlating with the fill level and / or limit level and / or the measured value through the housing to a receiver. The communication unit in particular, known communication standards such as Bluetooth (for example Bluetooth Low Energy), ZigBee, Wi-Fi (for example Wi-Fi HaLow) or cellular mobile radio standards such as 2G, 3G, 4G, 5G, NFC (for example LTE Cat 0 ) use. The communication unit can also be set up to provide an optical communication link. The communication unit can therefore have, for example, a Bluetooth module, an infrared module, a radio module, a WLAN module and / or some other information-transmitting module.

According to one embodiment, the sensor also has an energy supply unit which is arranged in the housing and which is set up to supply the sensor unit and the evaluation unit with electrical energy. The communication unit and / or other components of the sensor can also be supplied with electrical energy via the energy supply unit. For this purpose, the energy supply unit can have at least one battery, wherein the battery can be exchangeable or non-exchangeable.

According to a further embodiment, the energy supply unit has an accumulator. Furthermore, the power supply unit can have a charging unit for charging the accumulator. The accumulator can be used to supply the sensor unit, the evaluation unit and / or the communication unit with electrical energy. The operating time of the sensor can be extended by recharging the battery with the charging unit.

The energy supply unit can also have a device for determining the state of charge of the accumulator. The sensor can be set up to repeat the measurement of the fill level and / or limit level in the container after certain time intervals, wherein a time interval can depend on the state of charge of the accumulator. In other words, the sensor can be set up to change, adapt and / or vary a measuring rate as a function of the charge state of the accumulator. In particular, the sensor unit can be set up to emit the measurement signal less frequently when the state of charge of the accumulator is low. Accordingly, the evaluation unit can be set up to determine the signal correlating with the fill level and / or the limit level, the measured value and / or the parameter less frequently when the state of charge of the accumulator is low and / or reaches a definable or predetermined threshold. Furthermore, the communication unit can be designed to send the parameter, the signal and / or the measured value less frequently when the state of charge of the accumulator is low and / or reaches a definable or predetermined threshold.

According to a further embodiment, the charging unit of the energy supply unit has a solar cell and the housing of the sensor is designed to be transparent. For this purpose, at least a part of the housing can be made, for example, of a translucent plastic, such as an amorphous plastic, polycarbonate, Plexiglas, PMMA, polyamide or the like. As a result, the operating time of the sensor can advantageously be increased and / or the sensor can be operated independently over a long period of time. Alternatively or additionally, the housing or a part thereof can be made from such as polyethylene or polypropylene.

According to a further embodiment, the charging unit of the energy supply unit has a generator for generating electrical energy from vibrations. As a result, the operating time of the sensor can advantageously be increased and / or the sensor can be operated independently over a long period of time.

According to a further embodiment, the charging unit of the energy supply unit has a receiver for wireless energy transmission by means of electromagnetic induction. For example, the receiver can be compatible with the Qi standard for wireless energy transmission. This enables efficient and safe charging of the energy supply unit without the need for a cable for energy transmission.

According to a further embodiment, the charging unit of the energy supply unit has a thermoelectric generator for generating electrical energy from temperature differences. This, too, can advantageously increase the service life of the sensor.

Another aspect of the present disclosure relates to the use of a sensor, as described above and below, for measuring a fill level and / or limit level of a medium in a container, in particular in a plastic container. For example, the sensor can be used in an outdoor application, e.g. outdoors.

A further aspect of the invention relates to a sensor arrangement which has a sensor as described above and below. Furthermore, the sensor arrangement has a container, for example a plastic container, with a container wall. The sensor is arranged and / or welded on the outside of the container wall, so that the housing area of the sensor is arranged opposite the container wall.

Features, elements and / or functions of the sensor, as described above and below, can be features, elements and / or functions of the sensor arrangement as described above and below, and vice versa.

In the following, exemplary embodiments of the invention are described with reference to the figures.

Figure list

• 1A shows schematically a sensor arrangement with a sensor according to an embodiment.
• 1B FIG. 13 shows a detailed view of part of the sensor arrangement of FIG 1A .
• 2 to 7B each show a sensor according to exemplary embodiments.

Similar, similarly acting, identical or identically acting elements are provided with similar or the same reference symbols in the figures. The figures are only schematic and not true to scale.

Detailed description of exemplary embodiments

1A shows schematically a sensor arrangement 200 with a sensor 100 according to an embodiment. 1B shows a detailed view of part of the sensor arrangement 200 of the 1A .

The sensor is an example 100 of the 1A and 1B as a radar sensor 100 executed. Alternatively, the sensor 100 but also as an ultrasonic sensor 100 be executed. The same applies to the sensors 100 of the 2 to 7B .

The sensor arrangement 200 indicates the sensor 100 or radar sensor 100 and a container 202 on. The container 202 is at least partially with a medium 206 filled and has a container wall 204 which, for example, is a top of the container 202 can form. At least part of the container wall 204 on which the sensor 100 is attached is made of plastic. The entire container can also 202 be made of plastic.

The sensor 100 has a sensor unit 102 with an antenna 104 for emitting and / or receiving a measurement signal and / or radar signal. In particular, the antenna 104 one transmission signal emitted and one on the medium 206 reflected part of the transmitted signal can be received as a received signal.

Furthermore, the sensor 100 an evaluation unit 106 to determine a level and / or limit level of the medium 206 correlating signal based on the measurement signal and / or based on a transit time measurement between emission and reception of the measurement signal. The evaluation unit can also 106 determine a measured value which can be representative and / or indicative of the fill level, the limit level and / or the reaching of the limit level.

The sensor points further 100 a communication unit 108 on. The communication unit 108 is set up in particular for wireless data transmission. Via the communication unit 108 For example, the signal correlating with the level and / or limit level and / or the measured value can be transmitted wirelessly to a receiver. You can also use the communication unit 108 Data are received, such as parameterization data. The communication unit 108 can for example have a Bluetooth module, a WLAN module, an infrared module, a radio module or the like.

The sensor points further 100 a power supply unit 110 on which the sensor unit 102 , the antenna 104 , the evaluation unit 106 , the communication unit 108 and / or can supply other components with electrical energy. For example, the energy supply unit 110 have at least one battery and / or one accumulator. The energy supply unit can also 110 have a charging unit for charging the accumulator.

Furthermore, the sensor 100 a housing 112 on which the sensor unit 102 , the antenna 104 , the evaluation unit 106 , the communication unit 108 and the power supply unit 110 encloses, in particular completely encloses and / or hermetically seals. The case 112 can at least partially, in particular completely, be made of plastic.

The case 112 has a housing area 114 through which the measurement signal can be emitted and / or received. The housing area 114 can thus have an emission and / or reception area 114 of the sensor 100 (or the antenna 104 ) describe. The housing area 114 can thereby at least part of a housing side and / or a housing wall of the housing 112 describe. The sensor 100 is in this way on the container wall 204 arranged that the housing area 114 the container wall 204 opposite.

Furthermore, the housing 112 a fastening area formed at least partially from plastic 116 for fastening the sensor 100 on the container 202 on, the attachment area 116 one around at least part of the housing area 114 all-round plastic bar 120 (please refer 2 to 7B) having. The plastic bar 120 can here at least partially from the housing 112 protruding or flush with part of the housing 112 , for example with the housing area 114 , to lock. The sensor 100 of the 1A and 1B is on the container wall 204 welded on. Any plastic welding process can be used for this purpose. As part of the welding process to attach the sensor 100 on the container 202 becomes at least part of the plastic bar 120 and / or the container wall 204 melted, so that a cohesive welded connection 118 and / or weld seam 118 between sensor 100 and container 202 is trained. As explained in detail in the following figures, the plastic web runs around 120 the housing area 114 preferably completely, so that also the welded connection 118 and / or the weld 118 the housing area 114 completely circulates and / or encloses. This allows the sensor 100 reliably and permanently on the container 202 be attached. Also can through the welded connection 118 a space between the housing area 114 or housing 112 and the container wall 204 be sealed comprehensively and reliably.

The case 112 can be designed in one piece or in several parts. For example, the fastening area 116 Part of a first housing part and the housing area 114 can be part of a second housing part, wherein the first housing part and the second housing part can be detachably connected to one another.

2 shows a sensor 100 according to an embodiment. Unless otherwise stated, the sensor 100 of the 2 same features and elements as the sensor 100 of the 1A and 1B on.

The sensor 100 of the 2 is cylindrical and has a one-piece housing 112 made of plastic. The attachment area 116 of the housing 112 runs around the housing area 114 completely along an outer circumference of the housing 112 .

The plastic bar 120 of the fastening area 116 has a bevel 122 and / or a beveled surface 122 which serves as a weld seam preparation structure and / or is designed in the form of a weld seam preparation groove. A surface normal vector of the chamfer 122 is from the housing 112 directed away. The beveled face 122 and / or the plastic web 120 forms an edge 123 from which the housing area 114 runs around and / or surrounds in a ring. Using the bevel 122 , the edge 123 and / or the plastic bar 120 can the sensor 100 precisely, quickly and reliably by means of a plastic welding process on the container 202 attached. In the 2 Shown configuration of the plastic web 120 can be particularly advantageous for a hot gas welding process.

3A shows a sensor 100 according to an embodiment. 3B shows a sectional view of the sensor 100 of the 3A . Unless otherwise stated, the sensor 100 of the 3A and 3B the same features and elements as the sensors 100 of the figures described above.

In contrast to the sensor 100 of the 2 is at the sensor 100 of the 3A and 3B the plastic bar 120 as an energy director 120 educated. A geometry or shape of the energy director 120 can specify a welding direction here. The design of the plastic bar 120 as an energy director 120 can be particularly advantageous for ultrasonic welding processes and / or rotary friction welding processes.

The plastic bar 120 protrudes from the housing 112 from. One length 124 and / or height 124 to which the plastic bar 120 from the housing 112 protrudes can for example be around 1 mm to 20 mm. As in 3B recognizable, the plastic bar 120 has a triangular cross-section, the cross-section being symmetrical. The plastic bar 120 has two beveled surfaces arranged mirror-symmetrically to one another 122a , 122b on which under formation of an edge 123 run towards each other. The attachment area 116 , the plastic bar 120 and / or the edge 123 runs around the housing area 114 and / or surrounds it in an annular manner. With such a geometry of the fastening area 116 and / or the plastic web 120 can the sensor 100 precisely on the container 202 be welded.

4A shows a sensor 100 according to an embodiment. 4B shows a sectional view of the sensor 100 of the 4A . Unless otherwise stated, the sensor 100 of the 4A and 4B the same features and elements as the sensors 100 of the figures described above.

In contrast to the symmetrical design of the plastic bar 120 of the 3A and 3B , the sensor indicates 100 of the 4A and 4B a plastic bar 120 with a triangular cross-section, which is designed asymmetrically on one side. One bevel 122 and / or beveled surface 122 runs here starting from the housing area 114 forming an edge 123 obliquely outwards. A surface normal vector of the beveled surface 122 points in the direction of the housing area 114 . Alternatively, however, the beveled surface can also point outwards. An outside of the case 112 can thus be completely smooth from an upper end of the sensor 100 to a lower end of the sensor 100 run away. The attachment area 116 , the plastic bar 120 and / or the edge 123 runs around the housing area 114 and / or surrounds it in an annular manner.

5 shows a sensor 100 according to an embodiment. Unless otherwise stated, the sensor 100 of the 5 the same features and elements as the sensors 100 of the figures described above.

The sensor 100 of the 5 is analogous to the sensor 100 of the 2 designed, in particular with regard to the fastening area 116 , the plastic bar 120 , the beveled face 122 and / or the edge 123 . In contrast to the sensor 100 of the 2 , is the case 112 of the sensor 100 of the 5 cuboid and / or polyhedron-shaped. Otherwise, the same applies to the preceding figures (ia 2 ) Revealed.

6A shows a sensor 100 according to an embodiment. 6B shows a sectional view of the sensor 100 of the 6A . Unless otherwise stated, the sensor 100 of the 6A and 6B the same features and elements as the sensors 100 of the figures described above.

The sensor 100 of the 6A and 6B is analogous to the sensor 100 of the 3A and 3B designed, in particular with regard to the fastening area 116 , the plastic bar 120 , the beveled faces 122a , 122b and / or the edge 123 . In contrast to the sensor 100 of the 3A and 3B , is the case 112 of the sensor 100 of the 6A and 6B cuboid and / or polyhedron-shaped. Otherwise, the same applies to the preceding figures (ia 3A and 3B) Revealed.

7A shows a sensor 100 according to an embodiment. 7B shows a sectional view of the sensor 100 of the 7A . Unless otherwise stated, the sensor 100 of the 7A and 7B the same features and elements as the sensors 100 of the figures described above.

The sensor 100 of the 7A and 7B is analogous to the sensor 100 of the 4A and 4B designed, in particular with regard to the fastening area 116 , the plastic bar 120 , the beveled face 122 and / or the edge 123 . In contrast to the sensor 100 of the 4A and 4B , is the case 112 of the sensor 100 of the 7A and 7B cuboid and / or polyhedron-shaped. Otherwise, the same applies to the preceding figures (ia 4A and 4B) Revealed.

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

Claims (15)

Sensor (100) for determining a fill level and / or limit level of a medium (206) in a container (202), the sensor (100) having: a sensor unit (102) for emitting and / or receiving a measurement signal; an evaluation unit (106) for determining the fill level and / or the limit level based on a transit time determination of the measurement signal; and a housing (112) with at least one housing area (114) which is designed to be arranged opposite a container wall (204) of the container (202) for measuring the fill level and / or the limit level, the housing area (114) in such a way is designed so that the measurement signal can be transmitted through the housing area (114), wherein the housing further has a fastening area (116) for fastening the sensor (100) to the container (202), the fastening area (116) having a plastic web (120) running around at least part of the housing area (114) so that the The sensor (100) can be attached and / or fastened to the container (202) by melting at least part of the plastic web (120) by means of plastic welding. Sensor (100) Claim 1 , wherein the fastening area (116) and / or the plastic web (120) completely surrounds the housing area (114). Sensor (100) according to one of the preceding claims, wherein the plastic web (120) has at least one bevel (122, 122a, 122b) and / or has at least one beveled surface (122, 122a, 122b). Sensor (100) according to one of the preceding claims, wherein the plastic web (120) as an energy direction transmitter (120) for producing, by means of plastic welding, a materially bonded weld connection (118) and / or weld seam (118) between the sensor (100) and the container wall ( 204) is formed. Sensor (100) according to one of the preceding claims, wherein the plastic web (120) has a triangular cross section. Sensor (100) Claim 5 , wherein the cross section of the plastic web (120) is symmetrical. Sensor (100) Claim 5 , wherein the cross section of the plastic web (120) is asymmetrical on one side. Sensor (100) according to one of the preceding claims, wherein the housing (112) is designed in at least two parts with: - A first housing part, which has and / or forms the housing area (114), and - A second housing part which has and / or forms the fastening area (116); wherein the first housing part is detachably connected to the second housing part. Sensor (100) according to one of the Claims 1 to 7th wherein the housing (112) is made in one piece from plastic; and / or wherein the housing (112) is completely closed. Sensor (100) according to one of the preceding claims, wherein the housing (112) completely and / or permanently encloses the sensor unit (102) and the evaluation unit (106). Sensor (100) according to one of the preceding claims, wherein the housing (112) encloses the sensor unit (102) and the evaluation unit (1066) hermetically, in particular dust-tight, water-tight and / or airtight. Sensor (100) according to one of the preceding claims, wherein the sensor (100) is designed to be completely wireless to the outside; and or wherein the housing (112) has no cable bushing. Sensor (100) according to one of the preceding claims, further comprising: a communication unit (108) which is arranged in the housing (112) and which is set up to transmit a measured value correlating with the fill level and / or the limit level through the housing (112) to a receiver. Sensor (100) according to one of the preceding claims, further comprising: an energy supply unit (110) which is arranged in the housing (112) and which is set up to supply the sensor unit (102) and the evaluation unit (106) with electrical energy. Sensor (100) according to one of the preceding claims, wherein the sensor (100) is designed as a radar sensor or as an ultrasonic sensor.

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